Opinion by Judge GRABER; Concurrence in part and dissent in part by Judge TASHIMA
GRABER, Circuit Judge:
In this ease, we must decide, first, whether the discretionary-function exception, 28 U.S.C. § 2680(a), bars Plaintiff Jane Largent Alfrey’s action against the United States (Government) under the Federal Tort Claims Act (FTCA). Plaintiff alleges that the Government’s negligence resulted in the death of her husband, Thomas Martin Alfrey, an inmate at the Sheridan Federal Correctional Institution (Sheridan). Specifically, she alleges that the Government negligently assigned her husband to share a cell with an inmate serving a state sentence, who eventually killed him; negligently failed to remove her husband from the cell after his cellmate had threatened him; negligently failed to investigate the cellmate on a computer database; and negligently failed to find the murder weapon during a search of the cell following the threat. With one exception, we conclude that the Government’s conduct, even if negligent, involved the exercise of discretionary functions. The exception is Plaintiffs claim that the Government negligently failed to discharge a nondiscretionary duty to perform a “Central Inmate Monitoring” (CIM) evaluation before assigning the state prisoner to share Alfrey’s cell, as to which there are genuine issues of material fact. Consequently, 28 U.S.C. § 2680(a) bars Plaintiffs action except as to that claim.
We also hold that the district court properly dismissed Plaintiffs claims against several individual prison officials under Bivens v. Six Unknown Named Agents of the Federal Bureau of Narcot[560]*560ics, 403 U.S. 388, 91 S.Ct. 1999, 29 L.Ed.2d 619 (1971).
Accordingly, we affirm in part, reverse in part, and remand in the FTCA action and affirm in the Bivens action.
FACTUAL AND PROCEDURAL BACKGROUND
In 1978, Thomas Martin Alfrey was convicted in federal court of conspiring to distribute marijuana and of importing marijuana. He was released on parole in 1982. In December 1996, after violating conditions of his parole for a fourth time, Alfrey was confined at Sheridan. He was assigned to bunk 101 in the J-2 housing unit, where he remained until the time of his death.
On January 13, 1997, inmate Daniel Cas-to was assigned to Alfrey’s cell. Casto was a prisoner of the State of Oregon who was serving his state sentence at the Eastern Oregon Correctional Institution (EOCI), a state facility. While at EOCI, Casto sent a threatening letter to a judge. Casto was charged with a federal offense and transferred to Sheridan, apparently so that he would be closer to the United States District Court in Eugene, Oregon, where proceedings related to that charge would be heard.
In the early evening of January 18,1997, while walking to the prison library, Alfrey asked to speak with Corrections Officer Sullivan. Alfrey told Sullivan that he wanted to change cells because Casto had threatened to kill him, wrap him up in paper, and hang him on the door for Martin Luther King Day (January 20, 1997). Sullivan told Alfrey that he would ask Lieutenant Olsen to speak with him. Al-frey responded that he did not want to talk to Olsen; he simply wanted to be moved or to have Casto moved.
Sullivan reported the conversation to Corrections Officer Hurte.1 Hurte then telephoned Olsen and reported Alfrey’s concerns to him. Olsen asked whether Hurte thought that Alfrey’s request might be a “ploy” to move into another cell. Hurte said “yes.” Olsen decided not to move Alfrey, in part because Alfrey declined to speak to him personally. Olsen did not check “SENTRY” (a computer database) for information about Casto before making that decision.
After the conversation with Alfrey, Hurte and Sullivan and a third officer removed Casto from the cell and searched the cell. The search revealed no weapons, written threats, or other contraband.
At about 7:55 p.m. on January 18, Alfrey returned to his cell. At 8 p.m. another inmate reported that Casto was killing Al-frey. Officers immediately went to Alfrey’s cell, where they found Alfrey face down on the floor with a “rope” around his neck. The rope was constructed from what appeared to be torn sheets. None of the sheets in the cell was found to be torn.
Alfrey was transported to a local hospital. He died that evening. An autopsy determined that the cause of death was “strangulation with severe abdominal trauma and internal bleeding.” Casto was convicted of murdering Alfrey and is serving his sentence for Alfrey’s murder concurrently with the state sentence.
Plaintiff, acting as the personal representative of Alfrey’s estate, filed two actions in district court. One, an action under the FTCA, Case No. CV-99-1181-MA, alleged that the Government was liable because of its employees’ negligent con[561]*561duct. The other, a Bivens action, Case No. CV-99-68-MA, alleged that various prison officials had violated Alfrey’s First, Fifth, and Eighth Amendment rights by their conduct related to his death.
The two actions were consolidated, after which all Defendants filed a motion for summary judgment. The district court granted the motion in its entirety. The court ruled that 28 U.S.C. § 2680(a) bars all the FTCA claims because the challenged conduct involved the exercise of discretion. The court also concluded that the allegations in the Bivens action fail to state claims upon which relief can be granted. The court dismissed the case. Plaintiff filed a timely notice of appeal.
STANDARD OF REVIEW
We review de novo a grant of summary judgment. Burrell v. Star Nursery, Inc., 170 F.3d 951, 954 (9th Cir.1999). Viewing all evidence in the light most favorable to the non-moving party, we must determine whether there are any genuine issues of material fact and whether the district court correctly applied substantive law. Id. “Whether the United States is immune from liability in an FTCA action is a question of law reviewed de novo.” Fang v. United States, 140 F.3d 1238, 1241 (9th Cir.1998).
DISCUSSION
I. FTCA Claims
The FTCA waives sovereign immunity for specified tort actions arising out of the conduct of federal employees. 28 U.S.C. § 2674; Fang, 140 F.3d at 1241. That waiver, however, is limited. Id. Liability cannot be imposed if the tort claims stem from a federal employee’s exercise of a “discretionary function.” 28 U.S.C. § 2680(a). Title 28 U.S.C. § 2680(a) provides that the FTCA waiver of immunity does not extend to
[a]ny claim based upon an act or omission of an employee of the Government, exercising due care, in the execution of a statute or regulation, whether or not such statute or regulation be valid, or based upon the exercise or performance or the failure to exercise or perform a discretionary function or duty on the part of a federal agency or an employee of the Government, whether or not the discretion involved be abused.
We lack jurisdiction over any claim to which the discretionary-function exception applies. Sigman v. United States, 217 F.3d 785, 793 (9th Cir.2000).
We answer the question whether the discretionary-function exception bars a particular claim by applying a two-part test. Id. First, we must decide whether the challenged conduct is discretionary, that is, whether it “involv[es] an element of judgment or choice.” Fang, 140 F.3d at 1241 (citing Berkovitz v. United States, 486 U.S. 531, 536, 108 S.Ct. 1954, 100 L.Ed.2d 531 (1988)). “This element is not met Vhen a federal statute, regulation or policy specifically prescribes a course of action for an employee to follow.’ ” Id. (quoting Berkovitz, 486 U.S. at 536, 108 S.Ct. 1954). If the act is not discretionary, the government is not immune. Id.
Second, if the challenged conduct is discretionary, we “must determine whether that judgment is of the kind that the discretionary function exception was designed to shield.” Berkovitz, 486 U.S. at 536, 108 S.Ct. 1954. “Only those exercises of judgment which involve considerations of social, economic, and political policy are excepted from the FTCA by the discretionary function doctrine.” Sigman, 217 F.3d at 793. “The primary focus of the second part of the test is on ‘the nature of the actions taken and on whether they are [562]*562susceptible to policy analysis.’ ” Fang, 140 F.3d at 1241 (quoting United States v. Gaubert, 499 U.S. 315, 325, 111 S.Ct. 1267, 113 L.Ed.2d 335 (1991)). “When a statute, regulation or agency guideline allows a government agent to exercise discretion, it must be presumed that the agent’s acts are grounded in policy when exercising that discretion.” Weissich v. United States, 4 F.3d 810, 814 (9th Cir.1993) (citing Gaubert, 499 U.S. at 324, 111 S.Ct. 1267).
Plaintiff challenges the district court’s analysis of both parts of the test. First, she argues that there is a genuine issue of material fact as to whether the Government violated non-discretionary duties imposed by regulations or guidelines when it assigned Casto and Alfrey to the same cell and when it investigated Casto’s threat. Second, she asserts that the discretionary-function exception does not apply because the allegedly negligent conduct does not involve considerations of social, economic, or political policy.
A. Whether the Government had a nondiscretionary duty to perform a CIM evaluation of Casto or run a SENTRY check on him.
In support of its motion for summary judgment, the Government presented evidence, in the form of deposition testimony, that there are no regulations, policies, or other prison guidelines that impose mandatory duties on corrections officers related to cell assignment or the investigation of threats made by inmates. Plaintiff argues on appeal that other evidence creates two genuine issues of material fact.
(1) CIM Evaluation
Plaintiff first contends that the regulations governing CIM cases create a genuine issue of material fact precluding summary judgment on the question whether the Government was required to perform a CIM evaluation of Casto before assigning him to a cell. She argues that, under the regulations, a CIM evaluation for each inmate is mandatory; that the CIM evaluation is a component of the cell-assignment process; that the Government failed to perform the mandatory CIM evaluation; and that, as a result of that failure, Alfrey suffered harm. We agree that genuine issues of fact remain to be resolved.
The text of 28 C.F.R. § 524.73 makes it clear that CIM classification is, with listed exceptions, discretionary: “Except as provided for in paragraphs (a)(1) through (4) of this section, an inmate ... may be classified as a CIM case at any time.... ” 28 C.F.R. § 524.73(a) (emphasis added); see also 28 C.F.R. § 524.73(c) (providing that a CIM classification “may” be made at any level). Despite that usual discretion, the second exception may apply here. Some state prisoners receive a CIM designation “automatically”:
State prisoners. Appropriate staff in the Central Office or Regional Office designate state prisoners accepted into the Bureau of Prisons from state or territorial jurisdictions. All state prisoners while solely in the service of the state sentence are automatically included in the CIM system to facilitate designations, transfers, court appearances, and other movements.
28 C.F.R. § 524.73(a)(2).
Casto was a state prisoner “in the service of the state sentence.” It is not clear, however, whether he was accepted into Sheridan “solely” for that reason. He also was awaiting proceedings on a pending federal charge, and the record does not disclose whether the Government could or would have detained Casto at Sheridan had he not been serving a state sentence. It also is unclear whether, when a state prisoner is “automatically included in the [563]*563CIM system to facilitate designations, transfers, court appearances, and other movements,” a nondiscretionary duty arises to perform a CIM evaluation before making a cell assignment.
If Casto was accepted into Sheridan “solely in the service of the state sentence,” and if the regulation in such a circumstance imposes an obligation to perform a CIM evaluation when making a cell assignment, then the regulation imposed a nondiscretionary duty “automatically” to perform such an evaluation before placing Casto in Alfrey’s cell. If Casto was accepted into Sheridan for other or additional reasons, then a CIM evaluation was discretionary.
The CIM evaluation, if mandatory in the circumstance, could have affected Casto’s cell assignment and might have caused him not to be housed with Alfrey, a federal prisoner. As the comments accompanying the administrative rule explain:
Section 524.72(f),[2] “State Prisoners,” is new. This assignment includes persons, other than witness security cases, accepted into the Bureau of Prisons for service of their state sentences. This assignment provides the Bureau with a management tool to quickly identify state prisoners. The information is necessary for several reasons, including, where appropriate, to separate state prisoners.
Central Inmate Monitoring System, 47 Fed. Reg. 22000, 22001 (May 20, 1982) (emphasis added).
For these reasons, the district court erred when it ruled that there was no genuine issue of material fact as to whether the Government had a nondiscretionary duty to perform a CIM evaluation of Casto as part of his cell-assignment process.
(2) SENTRY Search
Plaintiff also asserts that there is a disputed issue of fact as to whether Olsen had a nondiscretionary duty to run a SENTRY search on Casto after Alfrey reported Casto’s threat. We disagree.
Plaintiff presented no evidence that prison employees had a duty to run a SENTRY search. Instead, she argued below (and repeats on appeal) that evidence that Olsen falsely reported that he had run a SENTRY search is evidence that Olsen may have thought that he had a duty to run such a search. Plaintiff then reasons that, if Olsen thought he should have run a SENTRY search, there is a disputed issue of material fact as to whether such a search was in fact mandatory under some federal regulation or prison policy. Even assuming that Olsen had such a motive, which is speculative,3 it is not evidence of the actual existence of a regulatory or policy-based duty to run a SENTRY search. The district court did not err in this regard.
B. Whether the Government’s challenged decisions involved social, economic, or political-policy considerations.
We turn now to the second part of the discretionary-function analysis. Plaintiff [564]*564contends that agents of the Government were negligent in responding to the report of Casto’s threat and that their negligent acts did not involve discretion of the kind that is protected by the discretionary-function exception. Specifically, she argues that the officers’ failure to search the cell in a way that would have enabled them to find the rope, and Olsen’s failure to run a search on SENTRY, were decisions that were grounded in occupational judgment, not in social, economic, or political judgment.
Plaintiffs argument fails for two reasons. First, federal regulations expressly give prison officials discretion in how to respond to reports of threats by inmates and in how to search cells. Therefore, it must be presumed that the officials’ choices in responding to the report of Cas-to’s threat were based in public policy. Gaubert, 499 U.S. at 324, 111 S.Ct. 1267; Weissich, 4 F.3d at 814. Second, even in the absence of a presumption, the challenged conduct of the prison officials involves the type of policy judgment protected by the discretionary-function exception.
This case resembles Calderon v. United States, 123 F.3d 947 (7th Cir.1997). In that case, as in this one, an inmate was attacked by his cellmate after the inmate had reported to officers that his cellmate had threatened him. Id. at 948. The inmate sued the United States under the FTCA, alleging that prison officials negligently had failed to separate the plaintiff from his cellmate and to prevent the attack. Id. at 948-49.
The Calderon court held that 28 U.S.C. § 2680(a) barred the inmate’s claims against the United States. It reasoned that federal regulations vested discretion in the prison officials to determine how to address the inmate’s report of the threat and that, therefore, it was required to presume that the officials’ conduct was grounded in policy considerations. Id. at 949-50. The court quoted 28 C.F.R. § 541.10:
“Staff shall take disciplinary action at such times and to the degree necessary to regulate an inmate’s behavior within ... Bureau rules and institution guidelines and to promote a safe and orderly institution environment.”
Id. at 949 (quoting 28 C.F.R. § 541.10) (emphasis added by the Calderon court). The court then observed that 28 C.F.R. § 541.13 prohibits an inmate from “ ‘[threatening another with bodily harm.’ ” Id. (quoting 28 C.F.R. § 541.13). The court further observed that 28 C.F.R. § 541.14 grants prison staff discretion to determine how to address a disciplinary violation: “ ‘[W]hen [the] staff witnesses or has reasonable belief that a violation of Bureau regulations has been committed by an inmate, and when staff considers informal resolution of the incident inappropriate or unsuccessful, staff shall prepare an Incident Report and promptly forward it to the appropriate Lieutenant.’ ” Id. (quoting 28 C.F.R. § 541.14(a)) (emphasis added by the Calderon court).
Relying on the emphasized text in the quoted regulations, the Calderon court held that the regulations vested discretion in the Bureau of Prisons to determine how to respond to the plaintiffs report of his cellmate’s threats. Id. at 949-50. For two reasons, the court further concluded that the type of discretion involved was of a kind protected by the discretionary-function exception. First, because the regulations explicitly confer discretion, the court presumed — as directed by the Supreme Court in Gaubert — that the officers’ conduct was grounded in policy considerations. Id. at 950. Second, the court concluded that “[i]t is clear that balancing the need to provide inmate security with the rights of inmates to circulate and socialize [565]*565within the prison involves considerations based upon public policy.” Id. at 951. Consequently, the court held that the government’s discretion not to separate the plaintiff from his cellmate was protected by the discretionary-function exception. Id.
We are persuaded by that reasoning. Under the regulations cited by the Calderon court, the officers at Sheridan had discretion to choose how to respond to a reported threat. Additionally, the regulations that govern cell searches confirm that the choice of the appropriate manner in which to search a cell is left to the discretion of the individual corrections officer. Title 28 C.F.R. § 552.10 authorizes the Bureau of Prisons to conduct “searches of inmates and of inmate housing and work areas.” It directs prison staff to “employ the least intrusive method of search practicable, as indicated by the type of contraband and the method of suspected introduction.” Id. That is, the regulation explicitly confers discretion on prison staff to decide how to search a cell in view of the particular threat presented and the practicalities of the situation. Because those regulations permit the prison staff to exercise discretion, we presume, in accordance with Gaubert and Weissich, that their exercise of that discretion here — in choosing how to search the cell and choosing not to run a SENTRY search — was grounded in policy considerations.
Moreover, independent of any presumption, that discretion is the kind protected by the discretionary-function exception. A prison official’s judgment about how extensively to search a cell involves a balancing of the potential risk, on the one hand, against the inmate’s interest in being free from overly intrusive searches, on the other. Similarly, to decide what steps to take in response to a reported threat, an officer must set priorities among all extant risks: the risk presented by the reported threat, along with the other risks that inevitably arise in a prison. Those types of decisions implicate social and public-policy considerations.
Our own holding in Sabow v. United. States, 93 F.3d 1445 (9th Cir.1996), confirms that Calderon supplies the correct analysis of whether the discretionary-function exception protects prison officials’ conduct in investigating a threat made by an inmate, including the officials’ method of searching a cell. There, we “recognized that the discretionary function exception protects agency decisions concerning the scope and manner in which it conducts an investigation so long as the agency does not violate a mandatory directive.” Vickers v. United States, 228 F.3d 944, 951 (9th Cir.2000) (summarizing the holding in Sabow, 93 F.3d at 1451-54) (emphasis added).
In Sabow, the family of a decedent sued the United States for negligent infliction of emotional distress stemming from an investigation of the decedent’s death by the Naval Investigative Services (NIS) and the Office of the Judge Advocate General (JAG). Sabow, 93 F.3d at 1449-50. We acknowledged that “some of the actions and inactions alleged by the Sabows, if true, represent alarming instances of poor judgment and a general disregard for sound investigative procedure.” Id. at 1454. Nevertheless, because federal investigations “clearly require investigative officers to consider relevant political and social circumstances in making decisions about the nature and scope of a criminal investigation,” we held that, in the absence of mandatory directives governing how to perform investigations,4 the discretionary-[566]*566function exception barred the plaintiffs’ claims relating to the negligent conduct of the investigation. Id. at 1453-54. That holding applies to any criminal or quasi-criminal investigation; an investigation into a death threat is an investigation of that nature.
Indeed, Plaintiff concedes — and the dissent agrees (dissent at 568-69) — that the choices whether to search the cell and whether to investigate Casto’s threat involved policy judgments. She asserts, however, that the prison officials’ subsidiary choice of the manner in which to search the cell, and the subsidiary decision not to run a SENTRY search, involved merely occupational or professional judgment. Ordinary occupational or professional judgments are not protected by the discretionary-function exception. Sigman, 217 F.3d at 796. We are not persuaded that the discretion involved here is properly characterized as ordinary occupational or professional judgment.
As we recognized in Sabow, investigations by federal officers clearly involve the type of policy judgment protected by the discretionary-function exception, and neither the facts in this case nor our analysis in Sigman dictates a contrary conclusion.
In Sigman, we held that the discretionary-function exception does not apply when “the claim is for negligence in performing a function that is analogous to functions performed by professionals in the private sphere every day.” 217 F.3d at 795-96. Thus, we held that the exception did not shield military physicians from liability arising from negligent medical practices. Id. at 796; see also Fang, 140 F.3d at 1242-43 (holding that the discretionary-function exception did not apply to medical negligence by federal Emergency Medical Technicians).
For three reasons, the Government’s choices about how to respond to Alfrey’s report of Casto’s threat are not like the daily functions of professionals in the private sphere:
• First, the acts of performing a cell search and of responding to a report of inmate misconduct are unique to the context of prisons. Those acts are core prison functions for which there are no private-sector analogues.
• Second, as discussed above, federal regulations grant prison officials discretion to determine how to search a cell and how to respond to a threat. As a result, the Government is entitled to a presumption that those determinations are based on policy considerations.
• Third, medical personnel are governed by professional and scientific standards that are independent of their federal employer and its policy judgments. By contrast, no external professional standards dictate how to perform a cell search in particular circumstances.5 Neither are there such standards informing prison officials of what steps ought to be taken to investigate reported inmate misconduct.
Of course, in some sense, the choices here involved professional judgment. For example, a prison official’s assessment of what type of search is needed is informed by professional training and experience. But that fact alone does not remove the decisions from the realm of policy-based judgments. Cf. Calderon, 123 F.3d at 950-51 (recognizing that even ordinary, “day to day” decisions of corrections officers involve “considerations of public policy”).
[567]*567Sadly, in this case, the officers’ choice of how extensively to search the cell did not result in their finding the rope. And, it is unclear whether Olsen’s performance of a SENTRY search might have helped to prevent Alfrey’s death. However, neither the result of those choices nor the possible negligence of those choices means that the choices themselves involved no policy judgment.
The cases cited by the dissent do not counsel a different result. As the dissent notes, one did not involve the discretionary-function exception, and the other was not an action under the Federal Tort Claims Act. (Dissent at 569 n. 2 & 570 n. 3.). Other important distinctions exist as well.
With respect to Indian Towing Co. v. United States, 350 U.S. 61, 76 S.Ct. 122, 100 L.Ed. 48 (1955): First, a lighthouse light is either on or off. There is no middle ground. Here, a search is either made or not made — but there are many ways to conduct a search. The existence of a range of options makes this ease different and gives rise to discretionary function immunity. Second, maintaining a physical object in good working order is ministerial, and it is subject to external, objective professional standards. As explained above, that is not the case here.
With respect to Huber v. United States, 838 F.2d 398 (9th Cir.1988): First, in that case the government’s choice did not implicate an allocation of resources. Id. at 400. By contrast, here, as the dissent recognizes (dissent at 573 n. 9), there were fights in the prison the night Alfrey died, and the length and nature of the cell search implicated the deployment of prison personnel. Second, in this case, a federal regulation (quoted above) expressly commits the decision of how to conduct searches to prison officials, under specified guidelines that require the officials to balance and consider the intrusiveness of a search to the prisoner, the type of contraband, and the method of suspected introduction of the contraband. In Huber we cited no similar regulation giving the Coast Guard discretion. Third, the kinds of interests that had to be balanced here (including allocation of resources, privacy concerns, and nature of the suspected threat) are more related to public policy than are questions (for example) of when to monitor a radio channel.
In short, the prison officials’ decisions related to how to search Alfrey and Cas-to’s cell and how to investigate the reported threat were grounded in policy considerations. The district court correctly held that 28 U.S.C. § 2680(a) bars Plaintiffs claims that the Government negligently failed to find the rope in the cell and negligently failed to run a SENTRY search on Casto.
II. Bivens Claims
The district court properly dismissed the constitutional claims raised against the individual defendants in the Bivens action.
Plaintiffs First Amendment and Eighth Amendment claims involve an element of improper motive. When subjective intent is an element of a Bivens claim, a heightened pleading standard applies. Harris v. Roderick, 126 F.3d 1189, 1195 (9th Cir.1997). A plaintiff must include “ ‘nonconclusory allegations containing evidence of unlawful intent.’ ” Id. (quoting Branch v. Tunnell, 937 F.2d 1382, 1386 (9th Cir.1991)).
The Bivens complaint in this case does not meet that standard. It contains nothing but conclusory allegations of unlawful intent and alleges no facts supporting an inference of unlawful intent. Plaintiffs memorandum in opposition to summary judgment did nothing to cure [568]*568the deficiency, and Plaintiff never asked to amend the complaint. The district court properly dismissed the First and Eighth Amendment claims.
The Fifth Amendment claim alleges that the individual defendants’ act of incarcerating Alfrey with Casto after they learned of Casto’s threat was “so discriminatory and blatantly wanton” that it violated Alfrey’s Fifth Amendment due process rights. However, the facts alleged by Plaintiff support, at most, a claim for negligence. Because a government official’s negligent conduct does not implicate the Due Process Clause, Daniels v. Williams, 474 U.S. 327, 334-36, 106 S.Ct. 662, 88 L.Ed.2d 662 (1986), the district court correctly dismissed that claim as well.
AFFIRMED in part, REVERSED in part, and REMANDED in Case No. CV-99-1181-MA; AFFIRMED in Case No. CV-99-63-MA. All parties to bear their own costs on appeal.