Michigan Rape Shield Law: What MCL 750.520j Prohibits and What Masi Changed

Michigan rape shield law is one of the most important evidentiary rules in a criminal sexual conduct case. It affects what the jury may hear, what the defense may investigate, how cross-examination is limited, and whether evidence of prior third-party abuse, sexual knowledge, or prior false allegations can be used at trial.

The statute is codified at MCL 750.520j. It applies in prosecutions brought under MCL 750.520b through MCL 750.520g, the Michigan criminal sexual conduct statutes. For a broader overview of the underlying CSC degrees, see our related guide to criminal sexual conduct in Michigan.

In July 2025, the Michigan Supreme Court issued People v Masi, a major decision interpreting the statute. The Court held that “sexual conduct” under MCL 750.520j includes both voluntary and involuntary behavior, including a child complainant’s involuntary viewing of pornography during prior alleged sexual abuse by a third party. The Court also overruled People v Morse to the extent Morse required a prior criminal sexual conduct conviction before a defendant could seek admission of prior-abuse evidence to explain a complainant’s age-inappropriate sexual knowledge.

What Does Michigan Rape Shield Law Actually Prohibit?

MCL 750.520j(1) excludes three categories of evidence in prosecutions brought under MCL 750.520b through MCL 750.520g:

• specific instances of the victim’s sexual conduct;
• opinion evidence of the victim’s sexual conduct; and
• reputation evidence of the victim’s sexual conduct.

The Michigan Supreme Court has interpreted the statute to bar evidence of all sexual activity by the complainant that is not incident to the alleged offense, subject to narrow exceptions. The Michigan Judicial Institute summarizes the rule in the same way, explaining that MCL 750.520j limits evidence related to a complainant’s past sexual conduct except for the two circumstances identified in the statute.

The purpose of the statute is not merely procedural. Michigan appellate courts have described MCL 750.520j as a legislative policy judgment that a complainant’s sexual conduct or sexual reputation is generally not legally relevant to character, truthfulness, or consent. That principle is especially important in sex crimes defense because the defense must distinguish between evidence that is legitimately probative and evidence the statute was designed to exclude.

What Are the Statutory Exceptions to Michigan Rape Shield Law?

MCL 750.520j recognizes two statutory categories of evidence that may be admitted if the judge finds the evidence material and determines that its inflammatory or prejudicial nature does not outweigh its probative value.

Outside those statutory categories, evidence otherwise barred by Michigan rape shield law may be admitted only when exclusion would violate the defendant’s constitutional rights, including the right to confrontation and the right to present a defense.

How Does a Defendant Seek to Admit Evidence Under MCL 750.520j?

The procedure is strict. If a defendant proposes to offer evidence described in MCL 750.520j(1)(a) or (b), the defendant must file a written motion and offer of proof within 10 days after arraignment on the information. The motion prepared by your Michigan Sex Crimes Defense Lawyer, should identify the evidence, explain the purpose for which it is offered, and establish why the evidence satisfies the statute.

The court may order an in camera hearing to determine whether evidence falling under the statutory categories is admissible. If new information is discovered during trial that may make the evidence admissible, the judge may order a supplemental in camera hearing.

The United States Supreme Court upheld Michigan’s notice-and-hearing procedure in Michigan v Lucas, rejecting a per se rule that the procedure violated the Sixth Amendment. However, preclusion is not automatic. If excluding the evidence would itself violate the defendant’s constitutional rights, the trial court must account for that constitutional limit.

Does Michigan Rape Shield Law Cover Involuntary Acts?

Yes, after People v Masi. Before Masi, Michigan courts had not definitively resolved whether “sexual conduct” under MCL 750.520j included involuntary behavior by a complainant, including conduct that occurred during prior abuse.

In People v Masi, the Michigan Supreme Court held that the plain meaning of “sexual conduct” includes individual behaviors, including acts and responses, that involve or are associated with sexual activities. The Court expressly held that this interpretation includes both voluntary and involuntary behavior. As a result, nonvolitional acts such as involuntarily viewing pornography during sexual abuse can constitute “sexual conduct” within the meaning of Michigan rape shield law.

This ruling matters because a defendant may not avoid MCL 750.520j simply by arguing that the complainant’s prior conduct was involuntary. If the evidence concerns sexual conduct, the statute applies unless a statutory exception or constitutional basis for admission is established.

What Did People v Masi Change?

The practical change in Masi concerns prior-abuse evidence offered to explain a child complainant’s age-inappropriate sexual knowledge. Under People v Morse, a defendant generally had to show that another person had been convicted of criminal sexual conduct involving the complainant and that the facts underlying the prior conviction were significantly similar to the charged conduct. That conviction requirement often prevented meaningful review where prior abuse was documented but never resulted in a conviction.

Masi overruled Morse to the extent Morse required a conviction related to the complainant’s prior sexual conduct. The Michigan Supreme Court held that the conviction requirement was unduly burdensome and should not be the determining factor for admitting evidence otherwise barred by MCL 750.520j.

The Masi framework does not mean prior-abuse evidence is automatically admissible. It means the absence of a prior conviction no longer ends the inquiry. A defendant still needs a developed offer of proof, a material defense theory, and a record showing that the evidence is necessary rather than merely helpful or cumulative.

Does Michigan Rape Shield Law Apply to Prior False Allegations?

No, not in the same way. Michigan courts recognize that evidence of a complainant’s prior false sexual assault allegations does not concern sexual conduct. It concerns credibility and, in some cases, a pattern of fabrication.

In People v Butler, the Michigan Supreme Court held that a defendant seeking to introduce a prior false allegation must make a sufficient offer of proof. The offer must present at least some apparently credible and potentially admissible evidence that the prior allegation was false. Once that threshold is met, the trial court must conduct an in camera evidentiary hearing. The evidence must still be evaluated under the Michigan Rules of Evidence and is not automatically admissible.

This distinction is critical. Michigan rape shield law protects against improper use of sexual-history evidence, but it does not give a witness immunity from impeachment based on a prior false accusation when the defense can satisfy the required evidentiary showing.

Practical Defense Implications After Masi and Butler

After Masi, defense counsel should evaluate prior-abuse evidence differently than before. The absence of a prior conviction no longer defeats the argument by itself. Counsel should instead focus on whether the prior act occurred, how closely it resembles the charged conduct, whether it is relevant to a material issue, whether it is necessary to the defense, and whether its probative value outweighs its prejudicial effect.

After Butler, counsel should also distinguish prior false allegations from prior sexual conduct. A false-allegation theory requires careful investigation. It is not enough to assert that a prior accusation was made. The defense must be prepared to show credible, potentially admissible evidence of falsity sufficient to justify an in camera hearing.

For clients facing CSC allegations, these rules make early defense preparation essential. A timely investigation can determine whether evidence is barred, whether a statutory exception applies, whether a constitutional motion is available, or whether the evidence falls outside MCL 750.520j entirely.