You’re staring at an MBE Evidence question about a sexual assault case, and suddenly the answer choices are throwing around terms like “rape shield rule” and “FRE 412.” Your mind goes blank. Is this about protecting the victim or the defendant? What evidence gets excluded, and what sneaks through the exceptions? If you’ve felt that panic, you’re not alone—the rape shield rule is one of the most tested and misunderstood Evidence rules on the bar exam.

Let’s break down exactly what FRE 412 does, when it applies, and how to spot the exceptions that the MBE loves to test.

What Is the Rape Shield Rule?

The rape shield rule under Federal Rule of Evidence 412 restricts the admissibility of evidence regarding a victim’s prior sexual behavior or predisposition in cases involving sexual misconduct. The rule exists to protect victims from having their sexual history paraded in front of a jury as a way to attack their credibility or suggest consent.

Here’s the core principle: in both civil and criminal cases involving alleged sexual misconduct, evidence of the victim’s other sexual behavior or sexual predisposition is generally inadmissible. This includes reputation evidence, opinion testimony, and specific instances of sexual conduct.

The MBE tests this rule relentlessly because it has narrow exceptions that students constantly mix up. You need to know what’s excluded by default and what can slip through the cracks.

When Does FRE 412 Apply?

The rape shield rule applies in two contexts:

Criminal cases involving any sexual misconduct charge (rape, sexual assault, sexual abuse, etc.)

Civil cases where a claim or defense involves alleged sexual misconduct (like a Title IX lawsuit or sexual harassment claim)

If the case doesn’t involve sexual misconduct as a central issue, FRE 412 doesn’t apply. A simple assault case where the victim happens to have a sexual history? The rape shield rule isn’t triggered. But the moment the charge or claim involves sexual behavior, FRE 412 kicks in.

What Evidence Does the Rule Exclude?

FRE 412 excludes two categories of evidence:

Evidence of the victim’s other sexual behavior: This means specific instances of sexual conduct with anyone other than the defendant. It also includes evidence offered to prove the victim engaged in other sexual behavior, even if it’s just reputation or opinion testimony.

Evidence of the victim’s sexual predisposition: This is broader. It includes any evidence suggesting the victim has a general tendency toward sexual activity—things like provocative clothing, sexual jokes, or testimony that the victim is “promiscuous.”

Here’s a classic MBE trap: A defendant in a rape case wants to introduce evidence that the victim was dressed provocatively at a bar earlier that night. Students think, “That’s just about clothing, not sexual behavior.” Wrong. That’s evidence of sexual predisposition, and it’s excluded under FRE 412.

The Criminal Case Exceptions

The rape shield rule isn’t absolute. In criminal cases, FRE 412 allows three narrow exceptions where evidence of the victim’s prior sexual behavior may be admitted:

Exception 1: Evidence of Specific Instances to Prove Someone Else Was the Source

If the defendant offers evidence of the victim’s sexual behavior with another person to prove that someone else—not the defendant—was the source of semen, injury, or other physical evidence, it may be admissible.

Example: The prosecution introduces DNA evidence showing semen was found on the victim. The defendant offers evidence that the victim had consensual sex with her boyfriend the night before the alleged assault to explain the DNA. This is admissible under the first exception because it’s offered to prove an alternative source of physical evidence.

Notice the rule is narrow: the evidence must be offered to explain physical evidence, not just to suggest the victim consents generally.

The defendant may introduce evidence of prior sexual behavior between the victim and the defendant to prove consent.

Example: The defendant is charged with rape. He claims the encounter was consensual and offers evidence that he and the victim had engaged in consensual sex on three prior occasions. This evidence is admissible to support his consent defense.

This exception only applies to prior conduct between the defendant and the victim. Evidence of the victim’s sexual behavior with third parties is still excluded, even if the defendant argues it shows a pattern of consent.

Exception 3: Evidence Whose Exclusion Would Violate the Defendant’s Constitutional Rights

If excluding the evidence would violate the defendant’s constitutional rights—typically the Sixth Amendment right to confrontation or the due process right to present a defense—the court may admit it.

Example: The victim testified that she had never engaged in any sexual activity before the alleged assault. The defendant offers evidence that the victim had consensual sex with another person a week earlier to impeach her credibility. This may be admissible because the victim “opened the door” by testifying falsely, and excluding the evidence would deny the defendant the right to cross-examine effectively.

This is the rarest exception and the one students overthink. The constitutional violation must be real and specific, not hypothetical. The MBE will usually make it obvious when this exception applies by having the victim make a sweeping false statement that the defendant can only rebut with sexual behavior evidence.

The Civil Case Exception

In civil cases, the rape shield rule is slightly more relaxed. Evidence of the victim’s sexual behavior or predisposition may be admissible if:

Its probative value substantially outweighs the danger of harm to the victim and unfair prejudice to any party.

This is essentially a reverse Rule 403 balancing test. Normally under Rule 403, evidence is excluded only if its prejudicial effect substantially outweighs its probative value. Under FRE 412 in civil cases, the proponent must show the probative value substantially outweighs the harm—a much harder standard to meet.

The MBE rarely tests the civil side of FRE 412, but when it does, watch for answer choices that try to sneak in evidence under regular Rule 403 balancing. That’s wrong. FRE 412 imposes a stricter standard in civil cases involving sexual misconduct.

Procedural Requirements: The Notice Rule

Here’s a procedural trap the MBE loves: even if an exception applies, the defendant in a criminal case must comply with FRE 412’s notice requirement.

The defendant must:

The court then holds an in camera hearing (closed to the public) to determine admissibility.

MBE tip: If a fact pattern says the defendant offers rape shield evidence without prior notice or a hearing, the evidence is inadmissible even if it fits an exception. Procedure matters.

Common MBE Traps with FRE 412

Trap 1: Evidence of sexual predisposition disguised as “context”

The defendant offers evidence that the victim was flirting with multiple men at a party before the alleged assault. Students think this is just background. It’s not—it’s evidence of sexual predisposition and is excluded.

Trap 2: Prior sexual behavior with third parties to show consent

The defendant offers evidence that the victim had consensual sex with someone else to argue she must have consented with him too. This is excluded. The exception only applies to prior conduct between the victim and the defendant.

Trap 3: Confusing FRE 412 with character evidence rules

FRE 412 operates independently of FRE 404 and FRE 608. Even if evidence of prior sexual behavior might be admissible under general character or impeachment rules, FRE 412 excludes it unless an exception applies. The rape shield rule is a specific exclusion that trumps other admissibility rules.

Trap 4: Assuming reputation evidence is always admissible

Some students think reputation evidence is fair game because it’s allowed in character evidence questions. Not here. FRE 412 explicitly excludes reputation and opinion evidence about the victim’s sexual behavior or predisposition.

What to Memorize for the MBE

When you see a sexual misconduct case on the MBE, immediately ask:

  1. Does FRE 412 apply? (Is this a criminal sexual misconduct case or a civil case involving a sexual misconduct claim?)
  2. What type of evidence is being offered? (Other sexual behavior? Sexual predisposition?)
  3. Does an exception apply?
    • Alternative source of physical evidence?
    • Prior conduct with the defendant to prove consent?
    • Constitutional violation if excluded?
  4. In criminal cases, did the defendant comply with notice requirements?

The MBE will often give you a fact pattern where the evidence technically fits an exception but the defendant failed to give notice. Don’t fall for it—the evidence is still excluded.

If you want all the rape shield rule elements, exceptions, and procedural requirements organized in one place for active recall, FlashTables covers FRE 412 in the Evidence subject along with the other 108 rules tested on the MBE. The two-column format makes it easy to drill the rule on one side and the exceptions on the other—exactly how you need to retrieve this information under time pressure.

Final Takeaway

The rape shield rule is narrow but powerful. Evidence of a victim’s prior sexual behavior or predisposition is excluded unless the defendant can point to a specific exception—and even then, procedural requirements must be met. The MBE tests this rule because students either overapply it (excluding everything) or underapply it (thinking any “relevant” evidence gets in).

Know the three criminal exceptions cold: alternative source, prior conduct with defendant, and constitutional violation. Know that civil cases require the probative value to substantially outweigh harm. And never forget the notice requirement in criminal cases. Master these elements, and you’ll spot the correct answer every time FRE 412 appears on your exam.