OPINION
STRINGER, Justice.
On May 7,1997, the body of Anne Marie Camp (Camp), the victim of an apparent homicide, was discovered on an abandoned farmstead in Clay County, Minnesota. A lengthy investigation eventually led authorities to suspect appellant and his wife, Jamie Dennis-Gianakos. The couple had married on February 14, 1997, at least in part for the purpose of invoking the mari[411]*411tal privilege if charged in a motel robbery they had staged 18 days earlier. Approximately two weeks after their marriage, appellant and Jamie were charged in the robbery; appellant confessed, but Jamie pleaded not guilty. Appellant and Jamie learned that Camp was the state’s key witness, and on May 1, 1997, Camp disappeared. Her body was found six days later.
On October 28, 1999, appellant and Jamie were indicted on charges of first-degree murder, conspiracy to commit first-degree murder, and aiding first-degree murder1 in Camp’s death. Jamie pleaded guilty as part of a plea bargain agreement and, over appellant’s marital privilege objection,2 testified for the state at appellant’s trial. Following a jury trial, appellant was convicted on all counts and sentenced to life in prison. The issues presented on appeal are whether the trial court erred in allowing appellant’s wife Jamie to testify against him despite his request that her testimony be excluded based on the marital privilege set forth in Minn.Stat. § 595.02, subd. 1(a), whether there is sufficient evidence to support his conviction, and whether the trial court erred in failing to instruct the jury sua sponte that a conviction cannot rest on the uncorroborated testimony of an accomplice. We reverse and remand.
At the time of her death, Camp was a friend of appellant and his wife Jamie. Camp also babysat for the couple’s children3 on occasion, including the night of January 27, 1997, when Jamie and appellant staged a robbery at a nearby motel where appellant was employed. Appellant confessed to the robbery, minimizing Jamie’s role in the crime.
On February 14, 1997, following a 17-month courtship, Jamie and appellant married. There is a discrepancy in the record regarding the motivation for and timing of their marriage: in appellant’s initial statement to authorities he indicated that the reason they got married when they did was so that they could not be forced to testify against one another; he later clarified his statement by claiming that what he meant was that avoiding adverse testimony was part of his reason for marrying Jamie, but that he also married her because he loved her. Jamie was more consistent in her testimony, acknowledging the marriage was a “sham” and claiming that the purpose of their marriage was to prevent her and appellant from having to testify against each other. The evidence also indicated that their marriage had been contemplated a year earlier when the couple began attending premarital classes at church, but the idea was dropped when Jamie became pregnant. Appellant said Jamie told him she “didn’t want to be fat in a dress” and that “it was just a piece of paper anyway.”
In any event, both admitted the marriage was at least partially motivated by their desire to take advantage of the privi[412]*412lege against adverse spousal testimony with respect to their anticipated robbery charges, ultimately filed against them on February 27, 1997. Jamie pleaded not guilty, and as her trial for the robbery approached, she and appellant became aware that Camp had made various statements to police regarding Jamie’s activities the night of the robbery. In fact, Camp was the only person who knew that Jamie had left her apartment on the night of the robbery. Jamie was ultimately convicted of robbery.
Initially, appellant and Jamie were not suspects in Camp’s murder and did not become the focus of the investigation until September 1998, more than a year later, when appellant’s family contacted authorities indicating that they had information regarding the Camp murder. In their recorded statements to police and in subsequent trial testimony, appellant’s parents explained how appellant had called them on the telephone crying and upset, purportedly having just read an entry in one of Jamie’s journals detailing the murder of Camp. Appellant’s mother claimed that appellant told her he was living with a murderer and that he thought his wife shot Camp. Appellant’s father testified that appellant, seemingly reading directly from an account of Camp’s murder written by Jamie, conveyed statements about giving Camp some pills that did not kill her, not being able to shoot her because she was stumbling around “woozy,” noting that her throat was slashed, and indicating that Jamie wore latex gloves while putting a butcher knife with appellant’s prints on it into a plastic bag and burying it.4 Appellant’s father encouraged appellant to save the book and go to the police with it.
Based on this information appellant’s home was searched and although some journals belonging to Jamie were seized, including one that made reference to Camp “haunting” her, none contained the specific statements appellant had shared with his parents.5 Nonetheless, authorities found appellant’s statements significant because at this time in the investigation, the only information that had been released to the public regarding Camp’s murder was that she was killed on or about May 1, 1997, and that she had suffered a gunshot wound to the head. Investigators knew that any additional information about Camp’s death, such as the fact that her throat had been slashed, would only be known to those somehow involved in the murder. But appellant’s statements regarding the pills confused investigators and prompted them to order a more in-depth lab analysis than that originally performed in conjunction with the autopsy.6 The results of this subsequent analysis revealed a concentration of doxy-lamine succinate in Camp’s system — a drug common in sleep aids — equal to approximately 85 times the normal prescribed dosage. Experts testified that such high quantities would have significantly debilitated Camp, physically and [413]*413mentally, making walking very difficult and perhaps even causing death.
On June 11, 1999, Jamie began serving her sentence at the Shakopee correctional facility for a probation violation. Investigators obtained permission to monitor Jamie’s calls and those coming in and out of the Gianakos home, hoping they might reveal new potential witnesses or other information helpful in solving the case. Investigators also interviewed Jamie but she remained silent on the advice of appellant. Eventually however, with the news that appellant’s parents had made statements to authorities implicating her and that a grand jury was being convened to seek a first-degree murder indictment against her and appellant, Jamie testified that she could no longer take the pressure. On October 21, 1999, Jamie confided in a fellow inmate about Camp’s murder, and the inmate subsequently contacted investigators and reported the details of the Camp murder as conveyed to her by Jamie.
On October 28,1999, a grand jury indicted appellant and Jamie for first-degree murder, conspiracy to commit first-degree murder, and aiding first-degree murder. Appellant pleaded not guilty and opposed the state’s motion to prohibit him from invoking the marital privilege. The,trial court ultimately ruled that Jamie could testify against appellant relying principally on federal case law recognizing exceptions to the marital privilege on grounds that the marriage was not entered into in good faith and that the couple was engaged in joint criminal activity.7
At appellant’s trial, Jamie testified against him as part of a plea agreement. According to Jamie, Camp’s potentially damaging statements to police regarding the motel robbery motivated them to take Camp out to an old farmstead appellant was familiar with on May 1, 1997, to scare her into changing her story. In preparation for the trip, Jamie testified that she purchased wine coolers she knew Camp liked hoping to “lighten the mood.” Jamie claimed she later saw appellant crushing sleeping pills into one of the wine cooler bottles to help “confuse” Camp during the planned confrontation, and that Jamie and appellant discussed how they could offer the bottle to Camp, already opened, so she would not be suspicious of the cap’s broken seal. Store records also indicate appellant purchased a .12 gauge shotgun on May 1, 1997, although Jamie claimed she was not aware of any gun until she saw appellant with it at the farmstead.
Jamie testified in detail as to what happened on the evening of May 1,1997, when she, appellant and their two children drove Camp out to the farmstead under the pretense of showing Camp some property appellant and Jamie were thinking of buying. Jamie explained that she gave Camp the drugged wine cooler to drink during the drive and that appellant pretended to be lost so the drugs and alcohol would have time to take effect. Jamie claimed that they arrived around 8:30 p.m., just as it was getting dark, and that Jamie, Cámp, and the children went into the abandoned farmhouse to look around until appellant eventually called for them to leave. Camp was walking very slowly by this time. As Jamie reached the car, she saw appellant come up behind Camp from the back of the house • with a shotgun in his hand. Jamie then heard the gun go off and saw Camp fall. According to Jamie, appellant proceeded to put on some rubber gloves, [414]*414instructed Jamie to do the same, and the two of them dragged Camp’s body face down behind the house. Once behind the house, they rolled the body over face up and appellant told Jamie to get a knife from the car and cut Camp’s throat. Jamie testified that she refused, went back to the car, and after noticing one of their kitchen knives under the front seat, looked up to see appellant standing over Camp and firing the shotgun toward her head.
Jamie testified that she and appellant then went home, Jamie drove to Camp’s apartment to retrieve Camp’s purse, and upon her return home appellant drove off with the purse. According to Jamie, appellant called about forty-five minutes later from his parent’s house to say that he had removed evidence from the farmstead that could connect them with the crime and that he had thrown the contents of Camp’s purse along the road. Jamie also testified that he told her he had “broken down” the gun and gotten rid of it. Appellant returned home around 12:30 a.m., and the couple later agreed that, if asked, they would say they were shopping that night.
Appellant testified to a very different story about the events of May 1, 1997. Contrary to Jamie’s testimony regarding a joint “plan,” appellant claimed he was not involved in any way with Camp’s death. Although his testimony revealed some confusion about whether or not he was with Jamie on the evening of May 1, 1997, he admitted to being present when the wine coolers were purchased and to buying the .12 gauge shotgun which he claimed was for Jamie’s protection during his impending incarceration for the motel robbery. Jamie contradicted appellant’s testimony on this point, stating that she didn’t like guns and was not concerned about security during appellant’s upcoming imprisonment.
In any case, appellant testified that Jamie and the girls then went to the house of Jamie’s mother near Detroit Lakes where she could practice using the new .12 gauge shotgun. According to appellant, Jamie returned late that evening without the gun, explaining that she was concerned about transporting it without a case. Meanwhile, appellant claimed he spent most of the evening — approximately 9:15 p.m. until 12:15 a.m. — keeping his father company in his mother’s absence. His parents testified to the same effect.
The medical examiner and others assisting in the investigation also testified at appellant’s trial, describing the condition of Camp’s body and the evidence found at the scene. A massive head wound was apparent to arriving authorities, and abrasion marks on Camp’s torso as well as grass caught under her pushed up bra and jacket suggested that the body had been dragged by the feet face down to its current position just north of the farmhouse. Both the medical examiner and an investigator with the Bureau of Criminal Apprehension testified that it was likely that at least two people were present at Camp’s murder because, considering Camp’s weight and the fact that she was probably already dead or at least unconscious at the time she was moved, it would have been extremely difficult for one person to drag her body to the place where it was found. Camp’s throat had been slashed and a shotgun wad was found entangled in her hair. Blood spatter analysis of the north wall of the farmhouse indicated that the trauma to the head was probably inflicted in approximately the same location and position in which the body was discovered, lying face up about four feet from the house. Shotgun pellets found in and near Camp’s body were consistent with those fired from a .12 gauge shotgun. A search of the surrounding area uncovered a pack of cigarettes, Camp’s wallet and. its scattered contents, and a pair of latex gloves.
[415]*415Routine lab analysis revealed a blood alcohol level of .031 grams per deciliter, a level consistent with having consumed about one wine cooler, and indicated the presence of a common antihistamine, doxy-lamine succinate, in her urine. At the time of the initial autopsy, the medical examiner concluded that a shotgun wound to the front of the head was the cause of death and that Camp was probably already dead when the neck wound was inflicted. Later in the investigation the high level of doxylamine succinate discovered in Camp’s system was added as a competing cause of death. ■
A farm neighbor who was outside on the evening of May 1, 1997, provided independent testimony of some events relating to the commission of the crime. He testified to seeing an unfamiliar car drive past at approximately 9-9:30 p.m., and turn into the farm where Camp’s body was later found. He subsequently heard a gun shot from that direction on his way into the house. Investigators measured tire tracks found at the scene in an attempt to identify a vehicle make and model, but no conclusive match could be made.
The jury ultimately found appellant guilty of all charges and he was subsequently sentenced to life in prison.
I.
We first consider whether our jurisprudence supports a denial of the marital privilege in cases where one of the reasons the couple chose to marry was to invoke the privilege, and whether there is an exception to the marital privilege under Minnesota law relating to spouses who engage in joint criminal conduct. The availability of a privilege established under statutory or common law is an evidentiary ruling to be determined by the trial court and reviewed based on an abuse of discretion standard. See Minn. R. Evid. 104; State v. Hooper, 620 N.W.2d 31, 38 (Minn. 2000). The determination whether a particular testimonial privilege or exception exists, however, is a question of law which this court reviews de novo. See Lewis v. Equitable Life Assurance Soc’y, 389 N.W.2d 876, 890 (Minn.1986); Star Trib. v. Bd. of Educ., 507 N.W.2d 869, 870 (Minn. App.), rev. denied (Minn. Dec. 22, 1993).
As a preliminary matter, we note that despite the statutory nature of Minnesota’s marital privilege,8 its roots are in the common law,9 and this court retains inherent power to adopt standards by judicial opinion relating to the admissibility of evidence in the interest of justice. See State [416]*416v. Erickson, 589 N.W.2d 481, 485 (Minn. 1999) (recognizing this court’s power not only to promulgate court rules, citing Minn.Stat. § 480.059, but also to “suspend the exercise of those rules where appropriate to ensure the proper administration of justice”).10 Thus, we agree with the dissent as to the nature of our authority, but the issue is whether it is appropriate, given our precedent, for this court to exercise that authority and declare the privilege against adverse spousal testimony unavailable. On this issue we disagree.
The social policy underlying the marital privilege was well set forth many years ago in State v. Feste:
The family is the basic unit of society as the cell is of the body. To cause strife between the parties to a marriage contract is to undermine this institution and thus to weaken the entire social structure. Courts and legislatures have recognized the burden which antagonistic interests impose upon the intimate relations of husband and wife and the harm to the public which results from marital discord, and have, as a general rule, refused for this reason to permit one spouse to testify against the other without the latter’s consent.
205 Minn, at 74-75, 285 N.W. at 86. The marital privilege in Minnesota is embodied in Minn.Stat. § 595.02, subd. 1(a). It provides that parties to a marriage cannot testify for or against each other without the other’s consent, and further, that neither spouse can be examined as to any communication made by one to the other during the marriage, absent the other’s consent. Id. In effect, the statute identifies two different types of marital privilege: 1) the privilege to prevent one spouse from testifying against the other during their marriage; and 2) the privilege to prevent one spouse from testifying at any time, during the marriage or after, concerning confidential interspousal communications during the marriage. Leecy, 294 N.W.2d at 283. The former, known as the privilege against adverse spousal testimony, is at issue here.11
A. The Sham Marriage Exception
The trial court denied appellant’s request to invoke the marital privilege in [417]*417part because both Jamie and appellant had indicated their marriage was motivated by a desire to be shielded from adverse testimony. The court therefore concluded that the interest protected by the privilege— that of preserving the integrity of the marriage — was outweighed by the competing interest in ascertaining the truth and presenting all relevant facts to the jury.12 The trial court relied heavily on federal case law recognizing a “sham marriage” exception to the privilege against adverse spousal testimony. See, e.g., United States v. Saniti, 604 F.2d 603, 604 (9th Cir.1979). While acknowledging the differences between the federal common law marital privilege and our corresponding statutory privilege, the trial court concluded that Minnesota had followed a similar progression of narrowing the privilege such that the recognition of similar exceptions was appropriate.
Appellant argues that the trial court’s reliance on federal jurisprudence is misplaced and that the trial court erred by recognizing exceptions to the marital privilege beyond those enacted by the legislature. Appellant further asserts that even if Minnesota’s statute did contain a “sham marriage” exception, it would not apply here because appellant’s marriage to Jamie was motivated by reasons other than merely the desire to invoke the privilege.
The state, on the other hand, claims that based on the evidence, the trial court reasonably concluded that the marriage of appellant and Jamie was disingenuous and entered into only to insulate the couple from having to testify against each other, initially in relation to the robbery charges and later with respect to Camp’s murder. The state asserts that upholding the marital privilege in this case would be absurd and contrary to this court’s previous rulings narrowly construing the statute to avoid creating “artificial barriers” to the truth. See Hannuksela, 452 N.W.2d at 676; see also Larson v. Montpetit, 275 Minn. 394, 402, 147 N.W.2d 580, 586 (1966) (“[EJvidentiary privileges constitute barriers to the ascertainment of the truth and are therefore to be disfavored and narrowly limited to their purposes * * *.”).
While this court has at least implicitly recognized the legitimacy of the marriage as a factor in determining whether to apply the marital privilege,13 we decline to conclude that the marriage at issue here was so clearly a sham that the privilege should be denied on that basis. We recog[418]*418nize that the record reveals that one of the primary reasons, perhaps the only reason, that Jamie entered into marriage was to take advantage of the statute prohibiting adverse spousal testimony. But the privilege rests with appellant, and appellant appears to have been motivated by several factors, among them perhaps the most conventional- — -his affection for Jamie. He argues that his actions as well as his words prove his motive for marriage — he began living with Jamie shortly after they met, he attended premarital classes with her at church long before the robbery, he adopted one of her children, he fathered his own child with Jamie, and he vainly shouldered full blame for the robbery to prevent her incarceration.
A review of our case law suggests that a strong showing is required to conclude that the marriage protected by the privilege is indeed so empty as to render the purpose of the privilege valueless. In State v. Frey, we concluded that the marital privilege statute protected a defendant husband from adverse spousal testimony even where a husband was being prosecuted for a premarital crime against his wife,14 76 Minn, at 530, 79 N.W. at 519, and in State v. Feste we held that a man contesting charges brought by his wife prior to their marriage that he was the father of her illegitimate child could preclude his wife from testifying against him at trial based on the marital privilege.15 205 Minn, at 76, 285 N.W. at 87. In no case have we ruled that a marriage is not worthy of the protection of the marital privilege, a statutory rule engrained in our state’s jurisprudence well over a century ago. See Pub. Stat. c. 84, § 53 (1859); Huot v. Wise, 27 Minn, at 69-70, 6 N.W. at 426. We conclude that on this record, the trial court abused its discretion in ruling that appellant’s marriage was a sham.
B. The Joint Participant Exception
We next turn to the determination of the trial court that the couple’s joint criminal activity constituted an additional basis to preclude application of the marital privilege. The “joint participant” exception, also borrowed from federal jurisprudence, bars the application of the marital privilege to a defendant who engaged in joint criminal activity with his or her spouse. See United States v. Van Drunen, 501 F.2d 1393, 1396 (7th Cir.1974). This exception is based on reasoning that the policy of preserving family harmony is not sufficiently important to justify assuring a criminal that he can enlist his or her spouse as an accomplice without fear of creating an adverse witness. Id.
Appellant again argues that it was improper for the trial court to recognize an exception to the testimonial privilege that was not identified in the statute, and that the legislature is in a better position to address public policy issues than the court.
We have not directly ruled on denial of the spousal privilege based on the joint participation of the spouses in criminal activity, although we have indirectly supported its rationale, see, e.g., Hannuksela, 452 N.W.2d at 676 (“‘A loyal spouse should not, in our view, become a [419]*419partner in crime with the blessing of the law bestowed through a strained construction of the statute which is said to be supported by a policy of promoting marital bliss’ ” quoting People v. Simpson, 39 Ill. App.3d 661, 350 N.E.2d 517, 524 (1976), rev’d on other grounds, 68 Ill.2d 276, 12 Ill.Dec. 234, 369 N.E.2d 1248 (1977)), and we have expressly recognized the strict application of a privilege where it .stands “as a barrier to testimonial disclosure,” Minneapolis Star & Trib. Co. v. Hous. & Redev. Auth. of Minneapolis, 310 Minn. 313, 320, 251 N.W.2d 620, 624 (1976) (citation and quotation omitted). Nonetheless, as noted above, our appellate courts have a history of recognizing the important social policy objective of preserving the marital relationship and deferring to the legislature to determine public policy with regard to family and marital issues.16 For example, we refer again to Hannuksela where we addressed as a first impression what acts or gestures are included in the term “communication” in Minn.Stat. § 595.02, subd. 1(a): the spouse cannot “be examined as to any communication made by one to the other during the marriage.” 452 N.W.2d at 675. Even though the defendant and his spouse were divorced at the time of trial, we stated: “[W]e feel free to adopt a construction which seems to best reflect the law’s social policy of protecting the marital relationship without erecting artificial ‘barriers to the ascertainment of truth.’ ” Id. at 676 (quoting Larson, 275 Minn, at 402, 147 N.W.2d at 586) (citation omitted). Later we again emphasized the importance of protecting marital confidences as the public policy served by section 595.02, subd. 1(a) and cited Wigmore on Evidence: “ ‘The privilege has for its object the security from apprehension of disclosure — a security of consequence of which confidences will be freely given and not withheld.’ ” 452 N.W.2d at 676 (quoting VIII J. Wigmore, Wigmore on Evidence § 2337 at 657 (McNaughton rev. 1961)). Thus, while we recognize the concern for establishing “artificial barriers to the truth,” our jurisprudence clearly weighs the balance in favor of the social policy of protecting the sanctity of the marriage. It is simply too great a departure from over 100 years of this court’s jurisprudence17 to adopt an exception to the marital privilege of this nature.
[420]*420The dissent argues that in this 100 years of case law nothing has been said about a joint participant exception to the privilege against adverse spousal testimony. This is precisely the point. We have not adopted such an exception and we decline to do so, preferring instead to defer a policy determination of this nature to the legislature, the branch of government historically responsible for addressing issues of public policy relating to the sanctity of the family. While we do not condone the ringing silence of the prime witness to the crime, given the strong policy supporting the privilege embodied in the common law and statute, we choose not to graft such an exception on to the privilege at this time. Accordingly, we hold that the trial court erred as a matter of law in its ruling that the alleged joint criminal activity of appellant and Jamie justified an exception to the marital privilege.
II.
In light of our ruling that the trial court erred in failing to preclude Jamie’s testimony over appellant’s objection, we consider whether that error was prejudicial. In making such a determination we apply a harmless error analysis. See State v. Juarez, 572 N.W.2d 286, 291 (Minn. 1997). If the verdict rendered was “surely unattributable” to the error, it is harmless beyond a reasonable doubt and the conviction may stand. State v. Keeton, 589 N.W.2d 85, 91 (Minn.1998); Juarez, 572 N.W.2d at 292. We conclude that admission of Jamie’s testimony was not harmless beyond a reasonable doubt.
A review of the record reveals that the majority of the testimony regarding the events of May 1, 1997, came from Jamie. Directly through her own testimony and indirectly through the testimony of her fellow inmate and confidant, Jamie provided virtually all the details of the murder, including the purchase of the wine coolers and how appellant added the potentially lethal sleeping pills, the manner in which they lured Camp to the murder site, the well thought-out events of the car ride, the shots fired by appellant, the dragging of Camp’s body to the back of the farmhouse, and the dumping of Camp’s purse along the road later that evening. Furthermore, Jamie provided information regarding appellant’s shotgun purchase, verified by authorities through store records. In short, it was Jamie’s statements that tied together many of the facts provided by the experts and investigators and linked them to appellant. We therefore cannot conclude that the wrongful admission of Jamie’s testimony was harmless beyond a reasonable doubt and that the verdict rendered was surely unattributable to that error. Accordingly, we reverse the conviction and remand for a hew trial.
We remand for a new trial consistent with our ruling, and because we do so, we do not address appellant’s final argument that the evidence presented at trial was insufficient to corroborate the testimony of Jamie, his alleged accomplice, and that the trial court erred in failing to instruct the jury sua sponte that a conviction cannot rest on the uncorroborated testimony of an accomplice.
Reversed and remanded.