A.B. v. County of San Diego

• Court: District Court, S.D. California
• Decided: July 31, 2020
• Docket: 3:18-cv-01541
• Status: Unknown

Opinion

1 2 3 4 5 6 7 8 UNITED STATES DISTRICT COURT 9 SOUTHERN DISTRICT OF CALIFORNIA 10 A.B., a minor, individually and as Case No.: 18cv1541-MMA-LL 11 successor in interest to decedent, Kristopher Birtcher, by and through her ORDER GRANTING IN PART AND 12 Guardian ad Litem, Ryan Birtcher; DENYING IN PART PLAINTIFFS’ MICHAEL BIRTCHER, individually; and DAUBERT MOTION; 13 CATHERINE BIRTCHER, individually, [Doc. No. 49] 14 Plaintiffs, ORDER DENYING PLAINTIFFS’ 15 v. DAUBERT MOTION;

16 COUNTY OF SAN DIEGO; SAN [Doc. No. 50] DIEGO SHERIFF’S DEPARTMENT; 17 WILLIAM D. GORE, Sheriff; DREW BEATTY; ADRIAN CARRILLO; ORDER DENYING PLAINTIFFS’ 18 ROLAND GARZA; JOSEPH DAUBERT MOTION; AND KODADEK; JOHN ROBLEDO; SCOTT 19 ROSSALL; FRANK STALZER; SCOTT [Doc. No. 51] WINTER; and DOES 1-10, inclusive, 20 ORDER GRANTING IN PART AND 21 Defendants. DENYING IN PART PLAINTIFFS’ DAUBERT MOTION 22 [Doc. No. 52] 23 24 25 26 27 28 1 Plaintiffs A.B., successor in interest to decedent, Kristopher Birtcher 2 (“Kristopher”), by and through her Guardian ad Litem, Ryan Birtcher, as well as 3 Catherine Birtcher and Michael Birtcher (collectively, “Plaintiffs”) bring this civil rights 4 action against the County of San Diego, the San Diego Sheriff’s Department, Sheriff 5 William D. Gore, and multiple individual San Diego County Sheriff’s deputies 6 (collectively, “Defendants”), alleging constitutional violations arising out of Kristopher’s 7 death on October 14, 2017. See Doc. No. 1. The parties have filed cross-motions for 8 summary judgment and relatedly move to exclude certain opinions proffered by each 9 other’s retained experts.1 See Doc. Nos. 44-47, 49-54. As relevant here, Plaintiffs move 10 to exclude certain opinions proffered by Defendants’ experts, Jeffrey Martin (“Martin”), 11 Dr. Gary Vilke (“Dr. Vilke”), Dr. Binh Ly (“Dr. Ly”), and Dr. Matthew Steiner (“Dr. 12 Steiner”). See Doc. Nos. 49, 50, 51, 52. For the reasons set forth below, the Court 13 GRANTS IN PART and DENIES IN PART Plaintiffs’ motions. 14 1. Legal Standard 15 Rule 702 of the Federal Rules of Evidence provides that expert opinion evidence is 16 admissible if: “(a) the expert’s scientific, technical, or other specialized knowledge will 17 help the trier of fact to understand the evidence or to determine a fact in issue; (b) the 18 testimony is based on sufficient facts or data; (c) the testimony is the product of reliable 19 principles and methods; and (d) the expert has reliably applied the principles and methods 20 to the facts of the case.” Fed. R. Evid. 702. The proponent of the expert opinion bears 21 the burden of establishing qualification, reliability, and helpfulness by a preponderance of 22 the evidence. Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 592 & n.10 23 (1993). Expert opinion testimony is reliable if it has a “basis in the knowledge and 24 experience of [the relevant] discipline.” Id. at 592-93 (“knowledge” requires more than a 25 subjective belief or an unsupported speculation; it requires an appropriate level of 26

27 1 The Court will address Defendants’ Daubert motions and the parties’ summary judgment motions in 28 1 validation). As the Ninth Circuit has explained:

2 Under Daubert and its progeny, including Daubert II, a district court’s inquiry 3 into admissibility is a flexible one. Alaska Rent-A-Car, Inc. v. Avis Budget Grp., Inc., 738 F.3d 960, 969 (9th Cir. 2013). In evaluating proffered expert 4 testimony, the trial court is “a gatekeeper, not a fact finder.” Primiano v. 5 Cook, 598 F.3d 558, 565 (9th Cir. 2010) (citation and quotation marks omitted). 6

7 “[T]he trial court must assure that the expert testimony ‘both rests on a reliable 8 foundation and is relevant to the task at hand.’” Id. at 564 (quoting Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 597 (1993)). “Expert 9 opinion testimony is relevant if the knowledge underlying it has a valid 10 connection to the pertinent inquiry. And it is reliable if the knowledge underlying it has a reliable basis in the knowledge and experience of the 11 relevant discipline.” Id. at 565 (citation and internal quotation marks 12 omitted). “Shaky but admissible evidence is to be attacked by cross examination, contrary evidence, and attention to the burden of proof, not 13 exclusion.” Id. at 564 (citation omitted). The judge is “supposed to screen 14 the jury from unreliable nonsense opinions, but not exclude opinions merely because they are impeachable.” Alaska Rent-A-Car, 738 F.3d at 969. Simply 15 put, “[t]he district court is not tasked with deciding whether the expert is right 16 or wrong, just whether his testimony has substance such that it would be helpful to a jury.” Id. at 969-70. 17 18 City of Pomona v. SQM N. Am. Corp., 750 F.3d 1036, 1043-44 (9th Cir. 2014). 19 “Challenges that go to the weight of the evidence are within the province of a fact finder, 20 not a trial court judge. A district court should not make credibility determinations that 21 are reserved for the jury.” Id. at 1044. 22 2. Discussion 23 a. Plaintiffs’ Motion to Exclude Certain Opinions Proffered by Jeffrey Martin 24 Plaintiffs move to exclude the following categories of opinions proffered by 25 Defendants’ police practices expert, Jeffrey Martin: (1) opinions about what video 26 recordings depict or what actually occurred during the deputies’ interactions with the 27 decedent, Kristopher; (2) foundational opinions regarding the use of digital video 28 evidence in officer-involved incidents; (3) medical opinions; (4) medical opinions 1 disguised as training opinions; (5) legal opinions; and (6) opinions regarding the states of 2 mind of the individual defendants and Kristopher. See Doc. No. 49-1 (“Martin Daubert”) 3 at 1. Defendants filed an opposition (Doc. No. 68 (“Martin Opp.”)), to which Plaintiffs 4 replied. Doc. No. 79 (“Martin Reply”). 5 i. Opinions Regarding What Videos Depict or What Occurred, 6 Foundational Opinions, and States of Mind Opinions 7 First, Plaintiffs argue that Martin’s expert reports contain opinions that should be 8 excluded as unhelpful to the jury and unreliable because they concern what is depicted in 9 video recordings and what actually happened during the incident in question. See Martin 10 Daubert at 2-3. Second, Plaintiffs argue that Martin’s foundational opinions are 11 unhelpful and intrude on the jury’s province of weighing credibility. See id. at 4. Third, 12 Plaintiffs assert that Martin’s opinions about the states of mind of the individual deputy 13 defendants (hereinafter, “deputies”) and Kristopher should be excluded as irrelevant and 14 unreliable. See id. at 8. Defendants respond that Martin’s opinions are appropriate 15 because they lay out the factual bases for Martin’s opinions as a police practices expert. 16 See Martin Opp. at 2-3. Therefore, according to Defendants, Martin “should be permitted 17 to identify and discuss scenes in video footage that are important to his analysis . . ..” 18 Martin Opp. at 3. 19 First, the Court finds that Martin is allowed to testify as to his observations that 20 form the basis for his conclusions, but the testimony may not amount to instructing the 21 jury as to what actually took place during the incident. Plaintiffs’ challenge here presents 22 a fine line that Defendants must draw in eliciting testimony from Martin. On one hand, it 23 would be unhelpful to the jury for Martin simply to take the witness stand and recount his 24 observations from the video evidence, since the jury is no less capable of viewing the 25 evidence and drawing their own conclusions. On the other hand, it would be odd for 26 Martin to present his ultimate conclusions in a vacuum without explaining how he 27 reached those conclusions. Rather, the proper approach is to allow Martin to explain the 28 basis for his opinions, which will undoubtedly be informed by his observations of the 1 video evidence. “[T]he disclosure of [such] basis evidence can help the factfinder 2 understand the expert’s thought process and determine what weight to give to the expert’s 3 opinion.” Williams v. Illinois, 567 U.S. 50, 78 (2012). Thus, the Court recognizes 4 Plaintiffs are correct that Martin’s testimony regarding his mere observations drawn from 5 the video evidence would be unhelpful to the jury. However, Martin’s testimony 6 regarding what he gathered from the video evidence, and how he applied his 7 methodology to form his ultimate conclusions, would be helpful to the jury. In this latter 8 scenario, Plaintiffs’ concerns that the jury will simply accept Martin’s views of the 9 evidence could be addressed on cross-examination by identifying any infirmities in the 10 basis for Martin’s conclusions. 11 The cases relied upon by Plaintiffs are inapposite. In their moving papers, 12 Plaintiffs rely on cases involving an audio/video expert who testified beyond the scope of 13 the methodology involved for making modifications to the evidence at issue in those 14 cases. See Lee v. Anderson, 616 F.3d 803, 808-09 (8th Cir. 2010); Zeen v. County of 15 Sonoma, No. 17-CV-02056, 2018 WL 3769867, at *2 (N.D. Cal. Aug. 9, 2018); Lam v. 16 City of San Jose, No. 14-CV-00877, 2015 WL, 6954967, at *2 (N.D. Cal. Nov. 10, 2015). 17 Moreover, the additional cases cited in Plaintiffs’ reply are similarly unpersuasive and, 18 upon close examination, have distinguishing factors that demonstrate why Martin should 19 be allowed to provide the basis for his ultimate conclusions. For example, in Sherrod v. 20 McHugh, the court had before it an issue in which two experts proffered testimony as to 21 the “proper interpretation” of video evidence. 334 F. Supp. 3d 219, 271 (D.D.C. 2018). 22 The court’s exclusion of such testimony does not persuade this Court to rule similarly 23 because the dispute here does not concern an expert opinion as to the proper 24 interpretation of the video evidence. Martin may proffer no such opinion, but he may 25 testify as to his observations that formed the basis of his conclusions.2 Similarly, in 26

27 2 The Court reminds Plaintiffs that a limiting instruction will also be available to alleviate their concerns 28 1 Barnes v. City of Pasadena, the court excluded an expert declaration proffering an 2 opinion that “enhanced photographs show the presence of a gun.” No. 10-CV-00470, 3 2011 WL 13143536, at *3 (C.D. Cal. May 5, 2011) (explaining that “[w]hat a photograph 4 depicts is readily visible to a lay person and is not a proper subject of expert testimony”) 5 (citing Fed. R. Evid. 702). Again, while Martin may not proffer an opinion as to the 6 proper interpretation of a video or photograph, he may discuss the video evidence in so 7 far as it forms the basis for his ultimate conclusions and opinions. The members of the 8 jury will certainly be able to view the video evidence and draw their own conclusions, 9 which may or may not overlap with Martin’s observations and affect the weight they 10 assign to Martin’s conclusions. 11 Second, Plaintiffs challenge Martin’s “foundational” opinions. Plaintiffs provide 12 one example: Martin opines that “digital video evidence does not necessarily reflect the 13 reasonable officers’ perspectives,” and “fail[s] to accurately represent the fears, emotions, 14 and stressors that might be affecting an officer’s reasonable perceptions and decision 15 making.” Martin Daubert at 4 (citing Doc. No. 49-2, Ex. D at 5-6). Plaintiffs contend 16 that such testimony improperly “instruct[s] the jury on how to weigh conflicting 17 evidence.” Id. However, Plaintiffs do not accurately characterize Martin’s opinion here, 18 as a review of his report shows that Martin is drawing on his expertise as a police 19 practices expert in an attempt to provide the jury with the perspective of a reasonable 20 officer. See Doc. No. 49-2, Ex. D at 5 (“[T]he use of digital video evidence must be put 21 into proper perspective.”). Thus, to assist the jury in its fact-finding function, Martin 22 discusses the “basic limitations of video evidence,” given that a “consideration[] in 23 evaluating peace officers’ force responses is that they ‘. . . must be judged from the 24 perspective of a reasonable officer on the scene.’” Accordingly, the Court will not 25

26 27 on Model Civil Jury Instructions, Manual of Model Civil Jury Instruction for the District Courts of the Ninth Circuit, § 1.11 (2017). 28 1 exclude such foundational opinions, as they do not infringe on the jury’s role of 2 determining credibility. 3 Lastly, Plaintiffs argue that the Court should exclude Martin’s discussions of the 4 subjective intent of Kristopher, and the deputies’ subjective beliefs or motivations, as 5 irrelevant and improper expert opinion evidence. See Martin Daubert at 4. Defendants 6 appear to argue that such discussions, like Martin’s observations of the video evidence, 7 form the basis for his opinions. See Martin Opp. at 1-2. Plaintiffs are correct that expert 8 testimony on one’s subjective state of mind and motives are impermissible. See Aya 9 Healthcare Servs., Inc. v. AMN Healthcare, Inc., No. 17-CV-205, 2020 WL 2553181, at 10 *5 (S.D. Cal. May 20, 2020) (expert opinions “on the intent, motives, or states of mind of 11 corporations, regulatory agencies and others have no basis in any relevant body of 12 knowledge or expertise.”) (internal quotations and citations omitted). The reason is 13 because such testimony “has ‘no basis in any relevant body of knowledge or expertise.’” 14 Id. at *6 (quoting Stone Brewing Co., LLC v. MillerCoors LLC, No. 18-CV-331, 2020 15 WL 907060, at *4 (S.D. Cal. Feb. 25, 2020)). Plaintiffs cite several examples indicating 16 that Martin intends impermissibly to opine on the states of mind and motives of 17 Kristopher and the deputies based on “inferences that [he] would draw from watching the 18 videos . . ..” Martin Daubert at 8-9; Doc. No. 49-2, Ex. F at 31-32. Such testimony has 19 no basis in any relevant body of knowledge or expertise and is therefore inadmissible. 20 In sum, for the reasons discussed above, the Court GRANTS Plaintiffs’ motion to 21 exclude Martin’s opinions on the states of mind and motives of Kristopher and the 22 deputies. However, the Court DENIES Plaintiffs’ motion to exclude Martin’s 23 observations of the video evidence that form the basis for his conclusions and his 24 “foundational” opinions. 25 ii. Medical Opinions 26 Plaintiffs further seek to exclude what they identify as impermissible medical 27 opinions, including those disguised as training opinions. See Martin Daubert at 4-7. 28 Defendants contend that “Martin, a sufficiently qualified police practices expert, should 1 be allowed to opine on what medical training deputies receive and/or what medical 2 knowledge a well-trained deputy is expected to possess.” Martin Opp. at 4 (citing 3 Arrington v. City of Los Angeles, No. 15-CV-03759, 2017 WL 10543403, at *7 (C.D. 4 Cal. 2017)). 5 The Court finds that Defendants have failed to carry their burden to demonstrate by 6 a preponderance of the evidence that the medical-related opinions proffered by Martin are 7 admissible. While it is true that Martin may opine on the medical training received or 8 medical knowledge possessed by a reasonable deputy, the opinions identified by 9 Plaintiffs go well beyond these topics. See Martin Reply 5-6. First, Martin’s opinions 10 about the “worst injury that Mr. Birtcher sustained” (Doc. No. 49-2, Ex. D at 21) or the 11 cause of a “fracture to Deputy Robledo’s right-ring finger” (id. at 12, 21) bear no relation 12 to the medical training received or medical knowledge possessed by a reasonable deputy. 13 Similarly, Defendants fail to establish the reliability of Martin’s opinion on 14 methamphetamine causing pupils to constrict. It is unclear to the Court whether Martin is 15 drawing on his expertise in police practices; Martin fails to state whether his experience 16 forms the basis for these opinions, or whether another source of specialized knowledge 17 does. Plaintiffs correctly point out that Martin vaguely describes the basis for his opinion 18 on pupil constriction as merely something that “some peace officers understand.” Id. at 19 30. Contrary to Defendants’ suggestion, Martin’s opinion here does not speak to the 20 training or knowledge that a “well-trained deputy” is expected to receive or possess. See 21 Martin Opp. at 4. Nor do Defendants attempt in their opposition to demonstrate whether 22 this opinion is reliable. 23 On the other hand, however, Martin’s opinion that a person’s ability to yell is an 24 “indication to a trained and reasonable deputy” that Kristopher was “able to adequately 25 ventilate” (see Doc. No. 49-2, Ex. D at 26), appears to be based on his qualifications as a 26 police practices expert. The distinction between this opinion and Martin’s opinion on 27 pupil constriction is that here, he indicates that a “trained and reasonable deputy” would 28 understand, based on their training, that a person can adequately ventilate if she can yell. 1 The opinion is permissible on this basis. Cf. Arrington v. City of Los Angeles, No. 15- 2 CV-03759, 2017 WL 10543403, at *7 (C.D. Cal. 2017) (“Based on [police practices 3 expert’s] training, . . . he may testify regarding the Los Angeles Police Department’s 4 practices for handling individuals who appear to be mentally unwell.”). 5 As for Martin’s opinions regarding what Plaintiffs identify as “the weight of 6 medical research and literature,” the Court finds the discussion to be admissible. Martin 7 Reply at 6 (citing Doc. No. 49-2, Ex. D at 27 & nn. 40-42). A review of the pertinent 8 portion of Martin’s report shows that the passages identified by Plaintiffs form the basis 9 for Martin’s ultimate opinion, that “[n]one of the deputies acted in a manner that would 10 cause them, or other . . . reasonable peace officers, to reasonably foresee . . . their . . . 11 actions in restraining Mr. Birtcher, increased the danger to him . . ..” Id. at 27. Plaintiffs 12 do not challenge Martin’s qualifications as a police practices expert, and Martin may 13 draw on this expertise to point out a lack of support for the proposition that a deputy uses 14 deadly force when she aims the TASER at the chest area. Id. Similarly, Martin may 15 draw on this same expertise to identify the support that exists for the proposition that 16 “contemporary [police] training is based on a considerable amount of scientific literature 17 that discredits theories that positional asphyxia, weight force on prone subjects, or 18 placing arrestees into prone positions, increases the risk of death or serious injury to 19 them.” Id. Contrary to Plaintiffs’ suggestion, an expertise in the medical field is not 20 necessary for Martin to be qualified to opine on these matters because Martin is not 21 providing a medical opinion. Rather, Martin may refer to any research and literature 22 supporting his discussion of the pertinent police practices. These bases for Martin’s 23 ultimate opinion on the foreseeability of increased danger fall squarely within his 24 qualification as a police practices expert. 25 In sum, the Court GRANTS IN PART Plaintiffs’ motion to exclude Martin’s 26 medical-related opinions identified above. However, the Court DENIES Plaintiffs’ 27 motion with respect to Martin’s opinions on Kristopher’s ability to breathe and “the 28 weight of medical research and literature.” Martin Reply at 6 (citing Doc. No. 49-2, Ex. 1 D at 27 & nn. 40-42). 2 iii. Legal Opinions 3 Lastly, Plaintiffs move to exclude Martin’s opinions regarding “what degree of 4 force a peace officer is legally entitled to use” and “whether the deputies followed clearly 5 established law.” Martin Daubert at 7.3 Defendants respond that Plaintiffs 6 mischaracterize the latter opinion and are wrong as to the propriety of the former opinion. 7 See Martin Opp. at 5-6. 8 “Though expert testimony is appropriate where ‘scientific, technical, or other 9 specialized knowledge will assist the trier of fact,’ expert testimony consisting of legal 10 conclusions is generally inappropriate.” CFM Commc’ns, LLC v. Mitts Telecasting Co., 11 424 F. Supp. 2d 1229, 1233 (E.D. Cal. 2005) (quoting Aguilar v. Int’l Longshoremen’s 12 Union Local # 10, 966 F.2d 443, 447 (9th Cir.1992) (upholding district court’s exclusion 13 of expert legal opinion as “utterly unhelpful”)). Under Federal Rule of Evidence 704(a), 14 “testimony in the form of an opinion or inference otherwise admissible is not 15 objectionable because it embraces an ultimate issue to be decided by the trier of fact.” 16 Although under this rule, expert witnesses can testify to the ultimate issue to be decided 17 by the jury, they may not testify to legal conclusions that are intertwined with the 18 ultimate issue. See Nationwide Transp. Fin. v. Cass Info. Sys., 523 F.3d 1051, 1058 (9th 19 Cir. 2008) (“Resolving doubtful questions of law is the distinct and exclusive province of 20 the trial judge”) (quoting United States v. Weitzenhoff, 35 F.3d 1275, 1287 (9th 21 Cir.1993)). “An expert witness therefore cannot offer testimony as to the reasonableness 22 of an officer’s actions and whether his use of force was appropriate under the facts of the 23 case.” Sanchez v. Jiles, No. 10-CV-9384, 2012 WL 13005996, at *31 (C.D. Cal. June 14, 24 2012) (citing Tubar v. Clift, No. 05-CV-1154, 2009 WL 1325952, *3 (W.D. Wash. May 25 26 3 Plaintiffs also moved to exclude Martin’s opinion that the “relative culpability” belongs to Kristopher 27 due to his prior drug use. See id. (citing Doc. No. 49-2 at 31:31-39). However, this issue is moot, as Defendants represent that they “will not be asking Martin to assign legal liability/culpability in this case, 28 1 12, 2009) (holding that a police practices expert was precluded from offering an opinion 2 as to whether an officer had “probable cause” to believe he was in imminent danger, 3 whether he acted “unconstitutionally,” and whether his use of force was objectively 4 unreasonable, as these were conclusions concerning ultimate issues of law)); see also 5 Shirar v. Guerrero, No. 1-CV-3906, 2017 WL 6001270, at *5 (C.D. Cal. Aug. 2, 2017) 6 (“Police practices experts may only testify as to whether an action conformed with a 7 reasonable standard of practice, not whether the particular officer’s action was reasonable 8 under the specific circumstances he faced.”) 9 First, the Court finds that Martin’s opinions are impermissible to the extent they 10 purport to establish the conduct at issue was “in accordance with the law” or consistent 11 with “clearly established law.” Plaintiffs cite several examples of such opinions. See 12 Martin Daubert at 7 (citing Doc. No, 49-2, Ex. D at 9:12-14,4 18:4-7, 19:1-5, 28:4-7). 13 These opinions impermissibly address ultimate issues of law: (1) whether the conduct at 14 issue was lawful, see Doc. No. 49-2, Ex. D at 9 (“Each of the deputies acted in a manner 15 that indicated their responses . . . were in accordance with the law.”); and (2) whether the 16 deputies’ conduct was in violation of clearly established law at the time the conduct was 17 performed.5 Defendants’ argue that Martin’s reference to “clearly established law” is 18 permissible because Martin does not analyze case law, argue that the clearly established 19 law was at the time, or “state that the deputies ‘followed’ such law.” Martin Opp. 5. The 20 21 4 The Court will not exclude the portion of Martin’s general opinion that “[t]he deputies were certified 22 as peace officers by California POST at the time of this incident and were performing discretionary functions within the course and scope of their duties.” Id. at 9:16-18. This opinion bears on Martin’s 23 expertise in police practice by asserting the conduct at issue was in conformance with certain police standards, not crossing into impermissible testimony on an ultimate issue of law. See Valtierra v. City of 24 Los Angeles, 99 F. Supp. 3d 1190, 1197 (C.D. Cal. 2015) (holding expert may opine on whether conduct 25 at issue was an appropriate use of force based on [his] expertise in POST and other law enforcement standards”). 26 5 This latter ultimate issue bears on whether the deputies are entitled to qualified immunity, while the 27 former issue bears on whether the deputies’ conduct was lawful, irrespective of the issue of qualified immunity. 28 1 argument is unpersuasive as it highlights a distinction without a difference. By opining 2 that the deputies conduct was performed in accordance with that of a reasonable officer 3 “aware of clearly established law” (see Doc. No. 49-2, Ex. D at 18-19, 28), Martin’s 4 opinions essentially tell the jury that the deputies’ conduct was in accordance with clearly 5 established law at the time.6 Cf. Valtierra v. City of Los Angeles, 99 F. Supp. 3d 1190, 6 1198 (C.D. Cal. 2015) (excluding an expert opinion as to whether “officers’ actions were 7 ‘objectively reasonable’” under the circumstances). 8 Second, the Court finds the remainder of the challenged opinions are admissible. 9 Martin’s opinion – that “there is no scientific or legal support” for the proposition that an 10 officer converts intermediate force to deadly force when targeting the chest with a 11 TASER – does not amount to an impermissible legal conclusion on an ultimate issue of 12 law. Rather, the opinion appears to be grounded in Martin’s expertise as a police 13 practices expert, as the opinion essentially will tell the factfinder that he is not aware of 14 any literature supporting the proposition regarding deadly force. Plaintiffs’ remedy for 15 such testimony is cross-examination aimed at discrediting the opinion. 16 In sum, as discussed above, the Court GRANTS IN PART Plaintiffs’ motion to 17 exclude Martin’s “legal opinions” bearing on “clearly established law.” However, the 18 Court DENIES the motion with respect to Martin’s opinion regarding a lack of literature 19 on TASER being a deadly force measure. Further, the Court DENIES as moot the 20 motion to exclude Martin’s opinion on “relatively culpability,” since Defendants admit 21 “eliciting such expert testimony would be inappropriate.” Martin Opp. at 5, n. 4. 22 /// 23 24 6 Because Plaintiffs have voluntarily dismissed their unlawful detention and arrest claim (see Doc. No. 25 54-6, Ex. BB at 4 of 4), the terms “reasonable suspicion” and “probable cause” no longer appear to be ultimate issues of law in this case. To the extent Martin references “clearly established law” while 26 opining on “reasonable suspicion” and “probable cause” (see Doc. No. 49-2, Ex. D at 18), the Court finds that even if the opinion does not address ultimate issues of law, it is excluded because its probative 27 value is substantially outweighed by the risk of unfair prejudice to Plaintiffs and jury confusion. See Fed. R. Evid. 403. Martin’s opinion can achieve the same purpose without such risks by merely 28 1 b. Plaintiffs’ Motion to Exclude Certain Opinions Proffered by Dr. Gary Vilke 2 Plaintiffs move to exclude the following categories of opinions proffered by 3 Defendants’ medical expert, Dr. Gary Vilke: (1) the spit sock used on Kristopher did not 4 contribute to his death; (2) there was no evidence the deputies failed to timely provide 5 medical assistance; (3) characterizations of the medical examiner’s conclusions about the 6 cause of Kristopher’s death; (4) the deputies had a need to use force to restrain Kristopher 7 because of “excited delirium syndrome” and the restraint was actually “protective;” (5) 8 Kristopher was breathing adequately because he was able to yell and move to some 9 extent; and (6) weight force applied to Kristopher’s legs, shoulders, and upper back had 10 no significant effect on ventilation. See Doc. No. 50-1 (“Vilke Daubert”) at 1. 11 Defendants filed an opposition (Doc. No. 65 (“Vilke Opp.”)), to which Plaintiffs replied. 12 Doc. No. 80 (“Vilke Reply”). 13 i. Spit Sock 14 Plaintiffs argue that Dr. Vilke’s opinion – that the spit sock did not contribute to 15 Kristopher’s death (hereinafter, “spit sock opinion”) – is unreliable because there is “too 16 large an analytical gap between” Dr. Vilke’s study on which he relies to form his opinion 17 and the facts of the case. See Vilke Daubert at 3. Defendants respond that Dr. Vilke’s 18 opinion is reliable even without the study, and in any event, his reliance on the study is 19 proper. See Vilke Opp. at 1-3. 20 Plaintiffs’ argument is unavailing. As Defendants recognize, Dr. Vilke does not 21 solely rely on his study to form the basis for his spit sock opinion. Dr. Vilke also bases 22 the opinion on: (1) the lack of clinical evidence that Kristopher was unable to breathe 23 through the spit mask, (2) the absence of any “published medical support for the 24 proposition that a spit sock has caused asphyxiation under any circumstance;” and (3) 25 “his extensive background and experience as both a physician and expert, and his 26 knowledge of the current landscape with respect to the medical research and literature 27 regarding spit socks.” Vilke Opp. at 1-2 (citing Doc. No. 50-3 at 12, 17-18). Plaintiffs’ 28 only response – that these additional bases for Dr. Vilke’s spit sock opinion are 1 “insufficient for such pseudo-scientific claim under Rule 702 (Vilke Reply at 1) – is 2 unpersuasive, as Plaintiffs cite not supporting authority. Rather, Plaintiffs’ arguments 3 bear on the weight of Dr. Vilke’s opinion, not its admissibility, and as such, they are 4 more appropriately reserved for vigorous cross-examination. See Primiano v. Cook, 598 5 F.3d 558, 564 (9th Cir. 2010), as amended (“Shaky but admissible evidence is to be 6 attacked by cross examination, contrary evidence, and attention to the burden of proof, 7 not exclusion.”). 8 Accordingly, the Court DENIES Plaintiffs’ motion to exclude Dr. Vilke’s spit 9 sock opinion. 10 ii. Medical Assistance 11 Plaintiffs next argue that Dr. Vilke’s opinion – that there is “no evidence” the 12 deputies failed timely to provide medical assistance (hereinafter, “medical assistance 13 opinion”) – should be excluded as “an impermissible legal argument . . ..” Vilke Daubert 14 at 5. Defendants respond that Plaintiffs are mischaracterizing Dr. Vilke’s opinion, and 15 that instead Dr. Vilke properly “analyzes the emergency medical assistance provided to 16 Birtcher” and opines “that the deputies were appropriate in their delivering of medical 17 care . . ..” Vilke Opp. at 4 (citing Doc. No. 50-3 at internal quotations omitted). 18 The Court finds that Dr. Vilke’s medical assistance opinion does not amount to an 19 impermissible legal opinion. As Defendants point out, an expert opinion “is not 20 objectionable just because it embraces an ultimate issue.” Vilke Opp. at 4 (citing Fed. R. 21 Evid. 704(a)). The Court is not persuaded that Dr. Vilke’s medical assistance opinion is 22 “a transparent legal conclusion,” as Plaintiffs contend (Vilke Reply at 1), merely because 23 it references there purportedly being “no evidence” showing the deputies failed to timely 24 provide medical assistance to Kristopher. Doc. No. 50-2, Ex. A at 12. This opinion bears 25 on the “objective reasonableness” standard applicable to Plaintiffs’ Fourth Amendment 26 claim (see Borges v. City of Eureka, No. 15-CV-00846, 2017 WL 363212, at *6 (N.D. 27 Cal. Jan. 25, 2017)); however, Dr. Vilke’s medical assistance opinion does not instruct 28 the jury to find that the provision of medical assistance in this case was objectively 1 reasonable. Further, for the first time in their reply, Plaintiffs raise the argument that Dr. 2 Vilke is not qualified to provide this opinion. See Vilke Reply at 1-2. This argument is 3 not only untimely, but it also misses the mark, as Defendants have shown Dr. Vilke is so 4 qualified, given his extensive experience in emergency medicine, the treatment of out-of- 5 hospital cardiac arrest, and the development of training for first responders (such as those 6 in law enforcement) “when dealing with persons exhibiting symptoms of excited 7 delirium.” Doc. No. 50-2, Ex. A at 17, 19; Doc. No. 69, Ex. A at 38-43. 8 Thus, the Court DENIES Plaintiffs’ motion to exclude Dr. Vilke’s medical 9 assistance opinion. 10 iii. Medical Examiner’s Conclusions of Cause of Death 11 Plaintiffs also move to exclude Dr. Vilke’s opinion agreeing “with the medical 12 examiner that Mr. Birtcher died from sudden cardiac arrest due to his methamphetamine 13 intoxication that occurred while he was restrained” (hereinafter, “medical examiner 14 opinion”). Vilke Daubert at 5. Plaintiffs argue that Dr. Vilke’s medical examiner 15 opinion is unreliable and unhelpful because it is actually inconsistent with the medical 16 examiner’s conclusions. See id. at 5-6. Defendants respond that any inconsistencies 17 between Dr. Vilke’s medical examiner opinion and the medical examiner’s conclusions 18 do not warrant exclusion, but rather any inconsistencies can be explored through cross- 19 examination. See Vilke Opp. 5-6. 20 The Court agrees with Plaintiffs. The basis for Plaintiffs’ position is that the 21 medical examiner (1) noted the “immediate cause” of death was “sudden cardiac arrest 22 while restrained,” and (2) listed “acute methamphetamine intoxication” as an “other 23 significant condition[] contributing to death but not resulting in the underlying cause” of 24 death previously noted, i.e., “sudden cardiac arrest while restrained.” Doc. No. 50-2, 25 Exs. D, E. Defendants argue that Plaintiffs’ point is belied by the medical examiner’s 26 finding that “acute methamphetamine intoxication” was a “significant condition[] 27 contributing to death . . ..” Vilke Opp. at 5 (quoting Doc. No. 50-1 at 5-6). Defendants 28 are correct that Dr. Vilke’s opinion is consistent with this incomplete quotation of the 1 medical examiner’s finding. However, there are two aspects of this “opinion” that render 2 it appropriate for exclusion as unhelpful to the jury. First, it is potentially misleading as 3 stated, since Dr. Vilke is agreeing with something that the medical examiner did not 4 exactly find. Second, even if Dr. Vilke changed his opinion to adopt the precise findings 5 of the medical examiner, this opinion would remain unhelpful to the jury, which will be 6 able simply to read and consider the medical examiner’s findings without Dr. Vilke’s 7 assistance. Therefore, the Court GRANTS Plaintiffs’ motion to exclude the medical 8 examiner opinion. 9 iv. Necessary and Protective Force 10 Next, Plaintiffs move to exclude Dr. Vilke’s medical opinions regarding the force 11 the deputies used to restrain Kristopher due to his exhibiting of excited delirium 12 symptoms, including the following (hereinafter, “necessary and protective force 13 opinions”): 14 • “Mr. Birtcher was demonstrating clinical findings consistent with excited delirium 15 syndrome (ExDS) that contributed to the need for the deputies to use force to 16 restrain him.” 17 • “And in the days before there were medications to treat these patients, the 18 mortality rate was reported at 75%.” 19 • “ExDS places the individual at increased risk for sudden death syndrome . . ..” 20 • “Mr. Birtcher demonstrated a number of symptoms consistent with ExDS.” 21 • “ExDS has a significant mortality rate and requires medical therapy to optimize 22 outcomes . . ..” 23 • “Law enforcement’s role is to secure a scene and get a violent or agitated or altered 24 person safely restrained so that medical personnel can then perform an assessment 25 and initiate treatment as appropriate. Thus, the behavior exhibited by Mr. Birtcher 26 was consistent with ExDS from his methamphetamine use and required the 27 deputies to use force in order to get him safely restrained in preparation for 28 medical evaluation by EMS.” 1 • “[T]he hobble restraint actually reduces and limits the ability of the restrained 2 individual to exert himself and produce lactic acid and consume oxygen, and thus 3 would actually be protective compared to ongoing running and struggling using 4 flexion and extension of the body’s large muscle groups.” 5 See Vilke Daubert at 6-7 (citing Doc. No. 50-2, Ex. A at 14-17). Plaintiffs take the 6 position that such opinions are irrelevant, unhelpful to the jury, and “unreliable due to an 7 utter lack of scientific basis.” Id. at 7. Defendants respond that Plaintiffs mischaracterize 8 Dr. Vilke’s necessary and protective force opinions, and in any event, the opinions are 9 admissible given Dr. Vilke’s uncontested qualifications and the relevance of the opinion. 10 See Vilke Opp. at 6-7. 11 First, the Court finds that Dr. Vilke’s necessary and protective force opinions are 12 relevant. The central issue in this case is whether the deputies used excessive first in 13 their encounter with Kristopher. Dr. Vilke’s necessary and protective force opinions bear 14 on whether the deputies’ use of force was reasonable in light of their observations of 15 Kristopher exhibiting signs of excited delirium syndrome. These opinions meet the low 16 bar for relevance under Federal Rule of Evidence 401. 17 Second, and similarly, the Court finds that Dr. Vilke’s necessary and protective 18 force opinions would be helpful to the jury. The members of the jury will be tasked with 19 evaluating whether the deputies’ use of force was objectively reasonable. Dr. Vilke’s 20 necessary and protective force opinions will provide the jury with helpful context as to 21 the actions of the deputies who purportedly observed Kristopher’s symptoms of excited 22 delirium syndrome. Plaintiffs argument – that the deputies used such force “because 23 [Kristopher] was under the influence and/or resisting them,” not “because of excited 24 delirium” – is insufficient. The undisputed facts that Kristopher was under the influence 25 of methamphetamine and resisting authority underscore the helpfulness as to Dr. Vilke’s 26 necessary and protective force opinions providing context for evaluating the use of force 27 here. 28 Lastly, the Court finds that Dr. Vilke’s necessary and protective force opinions are 1 reliable. “Because the Defendant has not challenged the qualifications of Plaintiffs’ 2 experts, the court focuses on the substance of Plaintiffs’ proffered expert testimony.” 3 Henricksen v. ConocoPhillips Co., 605 F.Supp.2d 1142, 1155 (E.D. Wash. 2009). Here, 4 the substance of the necessary and protective opinions, which Defendants accurately 5 summarize, is essentially as follows: (1) “the hobble restraint is generally an effective 6 tool that can decrease the chances of any suspect (whether or not they may be 7 experiencing excited delirium) over-exerting themselves,” and (2) “law enforcement is 8 expected to ‘get a violent or agitated or altered person safely restrained’ in order to allow 9 medical personnel to then safely evaluate them.” Vilke Opp. at 6-7 (citing Doc. No. 50- 10 2, Ex. A at 14, 17) (emphasis in original). Defendants are correct that these opinions 11 “explain why Birtcher may have been resisting as fiercely as he was and why the deputies 12 struggled to control him . . ..” Id. at 7. Plaintiffs do not argue that Dr. Vilke is 13 unqualified to give these opinions, but rather the opinions are not based on sufficient 14 facts or data. See Vilke Daubert at 7. Plaintiffs are incorrect. As discussed above, Dr. 15 Vilke has extensive experience in emergency medicine, the treatment of out-of-hospital 16 cardiac arrest, and the development of training for first responders (such as those in law 17 enforcement) “when dealing with persons exhibiting symptoms of excited delirium.” 18 Doc. Nos. 50-3 at 17, 19; 69, Ex. A at 38-43. Dr. Vilke may base his necessary and 19 protective force opinions on such experience, as well as the video evidence of the 20 deputies’ encounter with Kristopher, which he reviewed. See Doc. No. 50-2, Ex. A at 2. 21 In sum, the Court DENIES Plaintiffs’ motion to exclude the necessary and 22 protective force opinions of Dr. Vilke. 23 v. Adequate Ability to Breathe 24 Plaintiffs further move to exclude Dr. Vilke’s “opinion” that Kristopher was not 25 having any difficulty ventilating because he could yell and move to some degree 26 (hereinafter, “ventilation opinion”). See Vilke Daubert at 8 (citing Doc. No. 50-2, Ex. A 27 at 7). Plaintiffs argue that the opinion is unreliable. Id. Defendants counter that 28 Plaintiffs are actually criticizing the factual bases for Dr. Vilke’s ultimate opinion that 1 Kristopher did not die from positional asphyxia. See Vilke Opp. at 8. 2 The Court agrees with Defendants. A review of the pertinent portion of Dr. 3 Vilke’s expert report shows that the challenged portion is one basis (i.e., an observation 4 made by Dr. Vilke in reviewing the evidence) for his opinion that “[t]he restraining 5 process did not cause the sudden cardiac arrest and death [of] Mr. Birtcher.” Doc. No. 6 50-2, Ex. A at 7. Plaintiffs’ attack on this basis for Dr. Vilke’s opinion is better made on 7 cross-examination, as they go to the credibility of the testimony, not its admissibility. 8 See In re REMEC Inc. Sec. Litig., 702 F. Supp. 2d 1202, 1219 (S.D. Cal. 2010); 9 Hangarter v. Provident Life & Acc. Ins. Co., 373 F.3d 998, 1017 at fn14 (9th Cir. 2004) 10 (“The factual basis of an expert opinion goes to the credibility of the testimony, not the 11 admissibility, and it is up to the opposing party to examine the factual basis for the 12 opinion in cross-examination.”) (quoting Children’s Broad. Corp. v. Walt Disney Co., 13 357 F.3d 860, 865 (8th Cir. 2004)). Accordingly, the Court DENIES Plaintiffs’ motion 14 to exclude the ventilation opinion. 15 vi. Effect of Weight Force 16 Lastly, Plaintiffs move to exclude as unreliable Dr. Vilke’s opinion that “the 17 weight force on Birtcher was not significant enough to cause asphyxia” (hereinafter, 18 “weight force opinion”). Vilke Daubert at 8 (citing Doc. No. 50-2 at 8. Defendants 19 respond that the opinion is reliable as shown by Plaintiffs’ acknowledgment of the 20 research performed by Dr. Vilke regarding weight placed on subjects’ mid-back. See 21 Vilke Opp. at 8-9. 22 The Court finds that Dr. Vilke’s weight force opinion is reliable. As Defendants 23 recognize, Plaintiffs admit that Dr. Vilke performed research on the effect of weight 24 applied to subjects’ mid-back. See Vilke Daubert at 8-9. Yet, Plaintiffs’ challenge here 25 is grounded in the distinction between Dr. Vilke’s study on weight force applied to the 26 mid-back area of a subject, as opposed to the particular facts here involving weight force 27 applied to the legs, hips, shoulders, and upper back. See Vilke Daubert at 9-10. 28 Defendants correctly assert that “Rule 702 does not require an expert to find a study 1 linking the exact facts”; it only “require[s] the expert demonstrate a scientifically valid 2 basis for projecting the findings of a study to the proffered causal theory.” Vilke Opp. at 3 9 (quoting Henricksen, 605 F.Supp.2d at 1164-65); see also Primiano, 598 F.3d at 565, 4 as amended (“[T]he [Daubert] inquiry must be flexible,” and especially so where “[p]eer 5 reviewed scientific literature may be unavailable because the issue may be too particular, 6 new, or of insufficiently broad interest, to be in the literature.”). 7 Accordingly, Dr. Vilke’s weight force opinion is reliable and therefore Plaintiffs’ 8 motion to exclude it is DENIED. 9 c. Plaintiffs’ Motion to Exclude Certain Opinions Proffered by Dr. Binh Ly 10 Plaintiffs move to exclude the opinion of Defendants’ emergency medicine and 11 toxicology expert, Dr. Binh Ly, that “[t]he methamphetamine concentration detected in 12 Bitcher’s blood is highly typical of cases of severe methamphetamine intoxication 13 resulting in death and is in my opinion the cause of Kristopher Birtcher’s sudden cardiac 14 death while he was restrained by deputies.” Doc. No. 51-1 (“Ly Daubert”) at 1 (quoting 15 Doc. No. 51-2, Ex. A at 4). Defendants filed an opposition (Doc. No. 66 (“Ly Opp.”), to 16 which Plaintiffs replied. Doc. No. 81 (“Ly Reply”). 17 Plaintiffs argue that Dr. Ly’s opinion is irrelevant, unhelpful to the jury, and 18 unreliable. See Ly Daubert at 2-5. Defendants counter that Dr. Ly’s opinion is helpful to 19 the jury and reliable based on his unchallenged expertise in toxicology and because it was 20 not necessary for Dr. Ly to rule out all other possible causes of death. See Ly Opp. at 2- 21 5. 22 i. Toxicity Level 23 First, Plaintiffs move to exclude Dr. Ly’s opinion that “[t]he methamphetamine 24 concentration detected in Birtcher’s blood is highly typical of cases of severe 25 methamphetamine intoxication resulting in death” (hereinafter, “toxicity opinion”). Ly 26 Daubert at 1 (quoting Doc. No. 51-2, Ex. A at 4). Plaintiffs argue that this opinion “is 27 not supported by any reliable basis that was disclosed by Ly as required by Rule 28 26(a)(2)(B).” Ly Daubert at 3. Defendants respond that Plaintiffs’ complaint is of their 1 own making since they failed to question Dr. Ly during his deposition regarding the basis 2 of his toxicity opinion, and in any event, Plaintiffs’ own expert agreed with the toxicity 3 opinion. See Ly Opp. at 2-3. 4 The Ninth Circuit has explained that, if an expert did not conduct his or her own 5 research, independent of the litigation, on the subject of the testimony, the district court 6 must determine whether there exists any “objective, verifiable evidence that the 7 testimony is based on ‘scientifically valid principles.’” Daubert v. Merrell Dow Pharms., 8 Inc., 43 F.3d 1311, 1317–18 (9th Cir. 1995). Here, because it does not appear that Dr. Ly 9 conducted his own independent research on the toxicity levels of methamphetamine, the 10 Court will evaluate whether there exists objective and verifiable evidence of the validity 11 of his theory. Experts may demonstrate the scientific validity of a theory or technique by 12 showing that “the research and analysis supporting the proffered conclusions have been 13 subjected to normal scientific scrutiny through peer review and publication.” Id. at 1318. 14 Alternatively, testifying experts may also show the validity of their theory by explaining 15 “precisely how [the experts] went about reaching their conclusions and point[ing] to 16 some objective source—a learned treatise, the policy statement of a professional 17 association, a published article in a reputable scientific journal or the like—to show that 18 they have followed the scientific method, as it is practiced by (at least) a recognized 19 minority of scientists in their field.” Id. at 1319. 20 Here, the issue is whether Dr. Ly’s toxicity opinion is reliable when he did not 21 disclose the basis for his opinion, but it is nevertheless supported by the testimony of 22 Plaintiffs’ own expert. The Court is not persuaded by Defendants’ argument that 23 Plaintiffs waived their right to challenge the toxicity opinion as baseless simply because 24 they did not make an explicit inquiry at Dr. Ly’s deposition. Rule 26(a)(2)(B) clearly 25 provides, inter alia, that an expert’s “report must contain . . . a complete statement of all 26 opinions the witness will express and the basis and reasons for them . . ..” Fed. R. Civ. 27 P. 26(a)(2)(B) (emphasis added). As Plaintiffs argue, “Rule 26(a)(2) does not allow 28 parties to cure deficient expert reports by supplementing them with later deposition 1 testimony.” Ly Reply at 1 (quoting Ciomber v. Cooperative Plus, 527 F.3d 635, 642 (7th 2 Cir. 2008)). Moreover, the burden is on Defendants to demonstrate the reliability of Dr. 3 Ly’s opinion. See Daubert, 509 U.S. at 592 & n.10. “Contrary to [Defendants’] 4 argument, an opposing party is not required to file a motion to compel or depose the 5 expert in order to develop what her opinion is or the reasons for [her opinion].” In re 6 Cent. European Indus. Dev. Co., 427 B.R. 149, 158 (Bankr. N.D. Cal. 2009) (citations 7 omitted). 8 The Court is, however, persuaded by Defendants’ argument that the testimony of 9 Plaintiffs’ pathology expert, Dr. Omalu, supports Dr. Ly’s toxicity opinion. Dr. Omalu 10 testified that “Birtcher had a methamphetamine level of 3.6 milligrams per liter” which 11 “was within the toxic level.” Doc. No. 69, Ex. D at 156. When asked for the basis of his 12 opinion, Dr. Omalu could not provide one offhand, but testified that he would provide a 13 source for defense counsel, adding that the source would be a table found in “so many” 14 published papers. Id. at 157. In other word, according to Dr. Omalu, the toxicity levels 15 of methamphetamine are well known amongst those with similar medical expertise. 16 In light of this, the Court will not exclude Dr. Ly’s toxicity opinion even though 17 Defendants did not disclose the basis for this opinion. Pursuant to Federal Rule of Civil 18 Procedure 37(c), this Court has discretion to exclude evidence that is not submitted in 19 accordance with Rule 26(a). Fed. R. Civ. P. 37(c) (“If a party fails to provide 20 information . . . as required by Rule 26(a) or (e), the party is not allowed to use that 21 information . . . to supply evidence on a motion, at a hearing, or at a trial, unless the 22 failure was substantially justified or is harmless.”). Because Plaintiffs’ own expert 23 recognizes that the toxicity levels of methamphetamine are commonly known, the Court 24 finds that the nondisclosure is harmless. Indeed, Plaintiffs do not identify any prejudice 25 that they would suffer absent exclusion of the toxicity opinion. Accordingly, the Court 26 DENIES Plaintiffs’ motion to exclude the toxicity opinion of Dr. Ly. 27 ii. Causation 28 Plaintiffs also move to exclude Dr. Ly’s opinion that “[t]he methamphetamine 1 concentration detected in Birtcher’s blood . . . is in my opinion the cause of Kristopher 2 Birtcher’s sudden cardiac death while he was restrained by deputies” (hereinafter, “cause 3 of death opinion”). Ly Daubert at 2 (quoting Doc. No. 51-2, Ex. A at 4 (emphasis 4 omitted)). Plaintiffs argue that this opinion is unreliable because it “is not based on a 5 differential diagnosis or any other conceivably reliable methodology.” Id. at 4. 6 Defendants responds that this Circuit “does not require experts to use differential 7 diagnosis when reaching their conclusions.” Ly Opp. at 4 (citing Carrion v. United 8 States, No. 13–CV–0041, 2016 U.S. Dist. LEXIS 99519 at *9 (D. Nev. 2016)). 9 The Court finds Dr. Ly’s causation opinion is reliable and helpful to the jury. The 10 parties do not dispute that differential diagnosis is not a required methodology (see Ly 11 Reply at 2); however, Plaintiffs assert that Defendants “fail[ed] to offer any other 12 methodology that might establish reliability under the dictates of Rule 702.” Id. at 2. 13 Plaintiffs do not challenge Dr. Ly’s qualification as a toxicology expert, but nevertheless 14 argue that he “simply produces subjective conclusions and speculation and asks the Court 15 to take his word for it . . ..” Id. The argument is without merit. It is permissible for Dr. 16 Ly to draw on his extensive experience in medical toxicology and emergency medicine 17 (see Doc. No. 52-2, Ex. A at 1), and to offer the causation opinion based on his review of 18 the evidence. See id. at 1-2 (listing materials reviewed before formulating his opinions); 19 see also id. at 5 (“These opinions are based on review of the material noted above and 20 provided to a reasonable degree of medical certainty.”). 21 Plaintiffs nevertheless insist that the causation opinion is unreliable since Dr. Ly 22 failed to consider alternative potential causes of Kristopher’s death, namely, asphyxia. 23 See Ly Daubert at 4 (“Without any basis for ruling out other causes of death such as 24 asphyxia, Ly may not reliably opine as to the cause or primary cause of Birtcher’s 25 death.”) (citing Clausen v. M/V New Carissa, 339 F.3d 1049, 1058 (9th Cir. 2003)). 26 Clausen, however, does not require differential diagnosis. A review of Dr. Ly’s expert 27 report shows Dr. Ly’s unchallenged opinion that “[s]evere methamphetamine intoxication 28 and the associated extraordinary exertional behaviors may result in sudden cardiac arrest 1 absent any other factors.” Doc. No. 51-2, Ex. A at 4. The Court is not persuaded by 2 Plaintiffs’ argument that Dr. Ly may not reliably take the next step of opining that 3 Kristopher experienced sudden cardiac arrest as a result of his severe methamphetamine 4 intoxication. Similarly, his qualified opinion on causation would be helpful to the jury, 5 which will be tasked with deciding the material issue of Kristopher’s cause of death. 6 Accordingly, the Court DENIES Plaintiffs’ motion to exclude Dr. Ly’s cause of death 7 opinion. 8 Finally, it is not clear to the Court whether Dr. Ly intends to opine, as Plaintiffs’ 9 suggest, that “if Birtcher did not receive treatment for methamphetamine intoxication, he 10 would have died of a cardiac arrest or being struck by a vehicle . . ..” Ly Daubert at 4. 11 This “opinion” appears to have been elicited by Plaintiffs in Dr. Ly’s deposition (see 12 Doc. No. 51-2, Ex. B at 40), but it does not appear in his expert report. Given the lack of 13 clarity, the Court will DEFER ruling on this issue unless and until it arises during Dr. 14 Ly’s trial testimony.7 15 d. Plaintiffs’ Motion to Exclude Certain Opinions Proffered by Dr. Matthew 16 Steiner 17 Plaintiffs move to exclude the following opinions of Defendants’ addiction 18 medicine expert, Dr. Matthew Steiner: (1) Kristopher was under the influence of 19 methamphetamine and possibly opioids at the time of the incident; (2) Kristopher had a 20 stimulant use disorder at the time of the incident; (3) Kristopher was in the midst of a 21 severe relapse on methamphetamine and heroin soon after his release from prison; (4) 22 Kristopher was “pre-contemplative” and not proceeding toward sobriety at the time of his 23 death; (5) Kristopher had an extensive legal history closely tied to drug use; and (6) 24

25 26 7 That said, Defendants are hereby admonished that if Dr. Ly intends to offer the opinion at trial, the Court will likely sustain an objection to the opinion as outside the scope of his expert report. See Pajas 27 v. Cty. of Monterey, No. 16-CV-00945, 2019 WL 188660, at *3 (N.D. Cal. Jan. 14, 2019) (excluding opinion offered at deposition that was outside the scope of expert’s report). 28 1 Kristopher had a long-standing history of opioid use disorder. See Doc. No. 52-1 2 (“Steiner Daubert”) at 1. Defendants filed an opposition (Doc. No. 67 (“Steiner Opp.”), 3 to which Plaintiffs replied. Doc. No. 82. 4 i. Under the Influence Opinions 5 First, Plaintiffs move to exclude Dr. Steiner’s opinions that (1) Kristopher was 6 under the influence of methamphetamine at the time of the incident, and (2) Kristopher 7 was possibly under the influence of opiates at the time of the incident. See Steiner 8 Daubert at 2-3 (citing Doc. No. 52-2, Ex. A at 6-9 of 50). Plaintiffs contend that such 9 opinions are unhelpful to the jury and unreliable. See id. Defendants respond that 10 “Plaintiffs have no grounds to preclude Dr. Steiner from identifying [that Kristopher was 11 under the influence of methamphetamine at the time of the incident] or from explaining 12 methamphetamine intoxication to jurors.” Steiner Opp. at 1. 13 Dr. Steiner’s first opinion is that “[t]he evidence indicates within a reasonable 14 medical probability that Mr. Birtcher exhibited amphetamine intoxication at the time of 15 the incident.” Doc. No. 52-2, Ex. A at 7 of 50. Plaintiffs do not challenge Dr. Steiner’s 16 qualifications in addiction medicine, but nevertheless seek to exclude this opinion as 17 unhelpful to the jury because Plaintiffs do not dispute that Kristopher was under the 18 influence at the time of the incident. The Court finds the opinion admissible. As 19 discussed above, a central issue in this case is whether the deputies used excessive force 20 at the time of the incident. Therefore, Dr. Steiner’s opinion that Kristopher exhibited 21 amphetamine intoxication – as opposed to being merely under the influence of an 22 amphetamine – bears on this central issue and will help the jury determine the level of 23 force that might be appropriate during the incident. It is unlikely that the average juror 24 would be familiar with what signs of amphetamine intoxication are typically exhibited by 25 users under the influence, and therefore, the Court finds that the proffered opinion will 26 assist the jury. See United States v. Cazares, 788 F.3d 956, 977 (9th Cir. 2015) (“Experts 27 may be used to testify to matters outside the expected knowledge of the average juror.”). 28 Accordingly, the Court DENIES Plaintiffs’ motion to exclude this opinion. 1 Plaintiffs next challenge Dr. Steiner’s opinion that Kristopher was possibly under 2 the influence of opiates at the time of the incident. See Steiner Daubert at 3. A reading 3 of the relevant portion of Dr. Steiner’s report shows that, “[b]ased on the records,” it was 4 “unclear” to him “what evidence exists to suggest that decedent was under the influence 5 of opioids at the time of the incident.” Doc. No. 52-2, Ex. A at 10 of 50. Nevertheless, 6 Dr. Steiner stated “[i]t seemed quite possible given the evidence that there may have been 7 multiple substances contributing to the incident” because he “did not see negative 8 toxicology on opioids as provided in the medical records.” Id. Defendants do not 9 respond to Plaintiffs’ arguments regarding this opinion, and therefore fail to meet their 10 burden to demonstrate the reliability of the proffered opinion. Further, the Court agrees 11 with Plaintiffs that the opinion is unreliable as mere speculation and guesswork, given 12 that Dr. Steiner prefaced the opinion by noting the lack of clarity. See Daubert, 509 U.S. 13 at 590. Accordingly, the Court GRANTS Plaintiffs’ motion to exclude this opinion. 14 ii. Stimulant Use Disorder 15 Plaintiffs next move to exclude as unhelpful and unreliable Dr. Steiner’s opinion 16 that “[t]he evidence indicates within reasonable medical probability that Mr. Birtcher 17 exhibited a stimulant use disorder at the time of the incident” (hereinafter, “SUD 18 opinion”). See Steiner Daubert at 4-6 (citing Doc. No. 52-2, Ex. A at 10 of 50). 19 Defendants respond that Dr. Steiner’s SUD opinion is reliable because it is based on a 20 published and accepted methodology, “Fifth Edition of the Diagnostic and Statistical 21 Manual” (hereinafter, “DSM”). See Steiner Opp. at 4. Defendants further argue that Dr. 22 Steiner’s SUD opinion would help the jury make determinations on the credibility of 23 Plaintiffs’ testimony and their claims to damages. See id. at 2-5. 24 The Court finds that Dr. Steiner’s SUD opinion would assist the jury in making 25 determinations as to damages. Plaintiffs claim compensatory damages that include loss 26 of life, loss of enjoyment of life, and loss of financial support. See Doc. No. 1 at 42. Dr. 27 Steiner’s SUD opinion bears on the issue of such damages. Plaintiffs concede this point 28 in their motion. See Steiner Daubert at 4 (“Evidence on [a stimulant use disorder] . . . 1 would only be relevant to damages if there was a proper foundation that if he had not 2 died, Birtcher was likely to have had substance abuse issues in the future . . ..”). It is 3 unlikely that the average juror would be familiar with the effects of stimulant use disorder 4 on one’s life and familial relations, and therefore, the Court finds that the proffered 5 opinion will assist the jury. See Cazares, 788 F.3d at 977. 6 The Court also finds that Dr. Steiner’s SUD opinion is reliable. Plaintiffs argue 7 that Dr. “Steiner never evaluated Birtcher and relies solely on medical and arrest records, 8 the latter of which likely runs afoul of Rule 703.” Steiner Daubert at 5. Plaintiffs’ bald 9 assertion that Dr. Steiner impermissibly relies on arrest records is without merit. Federal 10 Rule of Evidence 703 provides that “An expert may base an opinion on facts or data in 11 the case that the expert has been made aware of or personally observed. If experts in the 12 particular field would reasonably rely on those kinds of facts or data in forming an 13 opinion on the subject, they need not be admissible for the opinion to be admitted.” 14 Plaintiffs provide no explanation as to why it would be unreasonable for Dr. Steiner to 15 rely on arrest records, among other records, in forming his SUD opinion. 16 Plaintiffs next argue that Dr. Steiner lacks factual support for his SUD opinion. 17 See Steiner Daubert at 5-6. This contention too is without merit. Dr. Steiner explained 18 he was opining based on the DSM methodology (see Doc. No. 52-2, Ex. A at 10 of 50), 19 then proceeded to opine that at least five of the 11 criteria for a finding of a stimulant use 20 disorder under the DSM methodology was present in the case of Kristopher. See id. at 21 10-14 of 50. Contrary to Plaintiffs’ suggestion, Dr. Steiner based his SUD opinion on 22 sufficient records demonstrating Kristopher’s well-documented history of substance 23 abuse and addiction, some of which indicates that he self-disclosed the history. See, e.g., 24 id., Appendix A at 31 of 50 (2/16/10 record of Kristopher under the influence of a 25 controlled substance and his admission of using drugs two days earlier), 33 of 50 26 (“Birtcher admitted to a long-term addiction to heroin.”), 36 of 50 (discussing substance 27 abuse history, including that Birtcher first used methamphetamine and heroin at age 12 28 and 13, respectively, and “[c]ontinued using both substances ‘as much as he could in a 1 day’” and “experimenting with ‘everything’ in the past”). For the same reasons, the 2 Court rejects Plaintiffs’ argument that Dr. Steiner’s “severe amphetamine use disorder 3 with amphetamine intoxication delirium” should be excluded as unreliable. See Steiner 4 Daubert at 6, n. 2. Likewise, this opinion is based on sufficient record evidence, 5 including multiple witness statements regarding Kristopher’s symptoms at the incident 6 and arrest records showing three weeks prior to the incident, Kristopher was arrested in 7 connection with the presence of drug paraphernalia. See Doc. No. 52-2, Ex. A at 14 of 8 50. 9 In sum, the Court DENIES Plaintiffs’ motion to exclude Dr. Steiner’s SUD 10 opinion and his related opinion regarding severe amphetamine use disorder with 11 amphetamine intoxication delirium. 12 iii. Relapse 13 Next, Plaintiffs move to exclude Dr. Steiner’s opinion that “Birtcher was in the 14 midst of a severe relapse on methamphetamine and heroin soon after his relapse from 15 prison” (hereinafter, “relapse opinion”). Steiner Daubert at 6 (citing Doc. No. 52-2, Ex. 16 A at 14-15 of 50). Plaintiffs argue that the relapse opinion is unhelpful to the jury and 17 unreliable. Id. Defendants respond that Dr. Steiner’s relapse opinion is helpful to the 18 jury on the issue of witness credibility and damages and is also reliable because it is 19 based on “the facts, his training and expertise, and arrived at through the methodology of 20 the DSM.” Steiner Opp. at 7. 21 First, the Court finds Dr. Steiner’s relapse opinion would be helpful to a jury on the 22 issue of damages. As with the SUD opinion, the average juror is unlikely to be familiar 23 with the effects of drug relapse on one’s life and familial relationships. Therefore, the 24 relapse opinion would assist the jury in making determinations regarding Plaintiffs’ claim 25 to damages. See Cazares, 788 F.3d at 977. 26 Second, the Court finds Dr. Steiner’s relapse opinion is reliable. Plaintiffs do not 27 challenge Dr. Steiner’s expertise in addiction medicine, but rather argue the relapse 28 opinion “appears to be based solely on Steiner’s transparent mischaracterization of the 1 September 27, 2017 arrest during which another man but not Birtcher was arrested for 2 possession.” Steiner Daubert at 6. That is not accurate. After considering Kristopher’s 3 history of drug abuse to offer the SUD opinion, Dr. Steiner referred to the records 4 indicating that Kristopher “had just served time on a three-year sentence in State Prison 5 for multiple charges which included armed robbery when he was detained for possession 6 of drug paraphernalia on 9/29/17.” Doc. No. 52-2, Ex. A at 14 of 50. Dr. Steiner then 7 considered that Kristopher “had only been unincarcerated for approximately three weeks” 8 when he was arrested with a companion for possession of drug paraphernalia with heroin 9 residue. See id.; see also id., Appendix A at 82 of 138; id., Ex. C at COSD000509-510. 10 The Court recognizes that the San Diego County Sheriff’s Department’s arrest record 11 indicates that the drug paraphernalia was found in the companion’s bag, rather than 12 Kristopher’s. See id., Ex. C at COSD000509-510. Nevertheless, at a minimum, the 13 arrest record indicates that Kristopher was arrested while associating with a companion 14 who admitted to using heroin earlier and possessed drug paraphernalia, including brown 15 residue (recognized to be heroin) in a glass vial. See id. This evidence, along with the 16 other evidence that Dr. Steiner considered, provides a sufficient basis for Dr. Steiner’s 17 relapse opinion, such that the Court finds it to be reliable. Accordingly, the Court 18 DENIES Plaintiffs’ motion to exclude the relapse opinion. 19 iv. Pre-Contemplative 20 Plaintiffs further contend that the Court should exclude Dr. Steiner’s opinion that 21 “Birtcher was not proceeding toward sobriety or likely to achieve it, but rather was ‘pre- 22 contemplative’ toward sobriety” (hereinafter, “pre-contemplative opinion”). Steiner 23 Daubert at 6 (citing Doc. No. 52-2, Ex. A at 15-18 of 50). Plaintiffs argue that Dr. 24 Steiner’s pre-contemplative opinion is unhelpful, unreliable, and impermissibly 25 speculates as to Kristopher’s subjective state of mind. See id. at 6-7. Defendants counter 26 that Dr. Steiner’s pre-contemplative opinion is reliable and would be helpful to the jury 27 on the issues of witness credibility and damages. 28 The Court finds Dr. Steiner’s pre-contemplative opinion would be unhelpful to the 1 jury. As discussed above, expert testimony may be helpful in aiding the jurors if it bears 2 on “matters outside the expected knowledge of the average juror.” See Cazares, 788 F.3d 3 at 977. Here, Defendants argue that the pre-contemplative opinion would be helpful for 4 the jury in assessing damages as they relate to Kristopher’s future sobriety. See Steiner 5 Opp. at 10. The Court is not persuaded the proffered opinion would be helpful, as it is 6 based on facts that the average juror is perfectly capable of understanding, along with the 7 implications on Kristopher’s chances of achieving sobriety. See Steiner Opp. at 8-9 8 (listing the facts on which the pre-contemplative opinion is based). In other words, 9 having Dr. Steiner review Kristopher’s failures of achieving sobriety would not be any 10 more helpful to the jury than presenting those underlying facts for the jury’s 11 consideration. Defendants may take this latter approach if they are concerned with the 12 Plaintiffs’ testimony as it relates to damages and Kristopher’s future sobriety. 13 Accordingly, the Court GRANTS Plaintiffs’ motion to exclude the pre-contemplative 14 opinion. 15 v. Legal History of Drug Use 16 Next, Plaintiffs move to exclude Dr. Steiner’s opinion that Kristopher has an 17 extensive legal history of drug use with no significant interruption in the offense history 18 nor any extended period of sobriety. See Steiner Daubert at 7-8 (citing Doc. No. 52-2, 19 Ex. A at 20 of 50). Defendants argue that the opinion is proper because it is based on 20 sufficient facts and Dr. Steiner’s expertise. See Steiner Opp. at 10-11. 21 The Court finds that Dr. Steiner’s opinion on the legal history of Kristopher’s drug 22 use would be unhelpful to the jury. A reading of Dr. Steiner’s opinion and the bases 23 therefor demonstrate that the opinion is simply based on Dr. Steiner’s review of 24 Kristopher’s arrest records and history of encounters with law enforcement. As with Dr. 25 Steiner’s pre-contemplative history, Dr. Steiner’s opinion on Kristopher’s legal history of 26 drug use would not be helpful to the jury because the average juror is perfectly capable of 27 reviewing the same underlying records and drawing her own conclusions. Therefore, the 28 Court GRANTS Plaintiffs’ motion to exclude this proffered opinion. 1 vi. History of Opioid Use Disorder 2 Plaintiffs further move to exclude Dr. Steiner’s opinion that Kristopher had a long- 3 standing history of opioid use disorder (hereinafter, “opioid opinion”). See Steiner 4 Daubert at 8. Defendants respond that Dr. Steiner’s opioid opinion would be helpful to 5 the jury in considering liability, witness credibility, and damages, and is reliably based on 6 sufficient facts and Dr. Steiner’s expertise. See Steiner Opp. at 11-12. 7 The Court finds that Dr. Steiner’s opioid opinion is admissible. Like Dr. Steiner’s 8 SUD opinion, his opioid opinion is reliably based on his expertise, the DSM 9 methodology, and record evidence documenting Kristopher’s history of drug use. See 10 Doc. No. 52-2, Ex. A at 23 of 50. Moreover, Dr. Steiner’s opioid opinion would be 11 helpful to the jury in considering Plaintiffs’ damages, since the average juror is unlikely 12 to be familiar with the effects of opioid use disorder on one’s life and familial relations. 13 See Cazares, 788 F.3d at 977. Therefore, the Court DENIES Plaintiffs’ motion to 14 exclude the opioid opinion.8 15 /// 16 /// 17 /// 18 /// 19 /// 20 /// 21 /// 22 /// 23 /// 24

25 26 8 The Court, however, cautions Defendants that Dr. Steiner’s opioid use opinion should not include his discussion of “the possibility of [Birtcher’s] opioid intoxication at the time of the incident . . ..” Doc. 27 No. 52-2, Ex. A at 23 of 50. Given the uncertainty that Dr. Steiner clearly expressed, any testimony from Dr. Steiner opining that Kristopher experienced opioid intoxication at the time of the incident 28 1 CONCLUSION 2 Based on the foregoing, the Court GRANTS IN PART and DENIES IN PART 3 Plaintiffs’ Daubert motions. Specifically, the Court: 4 1. GRANTS Plaintiffs’ motion to exclude Martin’s opinions on the states of mind 5 and motives of Kristopher and the deputies; GRANTS IN PART Plaintiffs’ 6 motion to exclude Martin’s medical-related opinions identified above; GRANTS 7 IN PART Plaintiffs’ motion to exclude Martin’s “legal opinions” identified above; 8 DENIES Plaintiffs’ motion to exclude Martin’s opinion regarding a lack of 9 literature on TASER being a deadly force measure; DENIES as moot Plaintiffs’ 10 motion to exclude Martin’s opinion on “relatively culpability,” since Defendants 11 admit “eliciting such expert testimony would be inappropriate,” (Martin Opp. at 5, 12 n. 4); DENIES Plaintiffs’ motion to exclude Martin’s opinions on Kristopher’s 13 ability to breathe and “the weight of medical research and literature” (Martin Reply 14 at 6 (citing Doc. No. 49-2, Ex. D at 27 & nn. 40-42)); and DENIES Plaintiffs’ 15 motion to exclude Martin’s observations that form the basis for his conclusions and 16 his “foundational” opinions; 17 2. GRANTS Plaintiffs’ motion to exclude Dr. Vilke’s medical examiner opinion; 18 DENIES Plaintiffs’ motion to exclude Dr. Vilke’s spit sock opinion; DENIES 19 Plaintiffs’ motion to exclude Dr. Vilke’s medical assistance opinion; DENIES 20 Plaintiffs’ motion to exclude Dr. Vilke’s necessary and protective force opinions; 21 DENIES Plaintiffs’ motion to exclude Dr. Vilke’s ventilation opinion; and 22 DENIES Plaintiffs’ motion to exclude Dr. Vilke’s weight force opinion; 23 3. DENIES Plaintiffs’ motion to exclude Dr. Ly’s toxicity opinion and cause of death 24 opinion; and DEFERS ruling on Plaintiffs’ motion to exclude the deposition 25 testimony elicited from Dr. Ly, since it is unclear whether Dr. Ly intends to opine 26 as such at trial; and 27 4. GRANTS Plaintiffs’ motion to exclude Dr. Steiner’s opinion that Kristopher was 28 possibly under the influence of opiates at the time of the incident; GRANTS 1 Plaintiffs’ motion to exclude the pre-contemplative opinion; GRANTS Plaintiffs’ 2 motion to exclude Dr. Steiner’s opinion regarding Kristopher’s legal history of 3 drug use; DENIES Plaintiff's motion to exclude Dr. Steiner’s opinion that 4 Kristopher was under the influence of amphetamine at the time of the incident; 5 DENIES Plaintiffs’ motion to exclude Dr. Steiner’s SUD opinion and his related 6 opinion regarding severe amphetamine use disorder with amphetamine intoxication 7 delirium; DENIES Plaintiffs’ motion to exclude Dr. Steiner’s relapse opinion; and 8 DENIES Plaintiffs’ motion to exclude Dr. Steiner’s opioid opinion. 9 IT ISSO ORDERED. 10 11 Dated: July 31, 2020 12 LHu- é hypllr 13 HON. MIC HAEL M. ANELLO United States District Judge 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28