Relevancy and reasons for excluding relevant evidence - Prio...

Learning Outcomes

This article explains the admissibility and exam-focused analysis of prior sexual misconduct evidence under the Federal Rules of Evidence, including:

• Identifying when FRE 413, 414, and 415 apply in criminal and civil cases involving sexual assault or child molestation and distinguishing these rules from the general character framework in FRE 404.
• Defining what qualifies as an “offense of sexual assault” or “child molestation,” who the rules apply to (criminal defendants or civil parties), and what forms of prior acts evidence may be used.
• Applying the notice requirements, conditional relevance standards, and Rule 403 balancing to decide whether to admit or exclude prior sexual misconduct evidence.
• Comparing FRE 413–415 with rape-shield protections under FRE 412, hearsay limits, and the availability of limiting instructions under FRE 105.
• Spotting common MBE traps, such as attempts to use FRE 413–415 in non–sexual-misconduct cases, with nonparty actors, or where the evidence is offered solely to show that someone is a “bad person.”
• Practicing structured reasoning through MBE-style fact patterns to determine the correct rule, the purpose for which the evidence is offered, and the strongest admissibility argument on exam day.

MBE Syllabus

For the MBE, you are required to understand the exceptions to the general prohibition against character evidence that apply in sexual misconduct cases, with a focus on the following syllabus points:

• Distinguishing the special rules for prior sexual misconduct (FRE 413–415) from the general character evidence framework in FRE 404.
• Identifying when FRE 413 (sexual assault) and FRE 414 (child molestation) apply in federal criminal prosecutions.
• Recognizing that under FRE 413 and 414, evidence of the defendant’s prior commission of such offenses is admissible for any relevant purpose, including propensity.
• Applying FRE 415 in civil cases “concerning” sexual assault or child molestation, and understanding who must be the party against whom the evidence is offered.
• Knowing the timing and content of the notice requirement for evidence offered under FRE 413–415.
• Analyzing all FRE 413–415 evidence under FRE 403, including the factors courts weigh in deciding whether probative value is substantially outweighed by the danger of unfair prejudice.
• Understanding the interaction between FRE 413–415 and FRE 404(b), FRE 412 (rape shield), hearsay rules, and limiting instructions under FRE 105.

Test Your Knowledge

Attempt these questions before reading this article. If you find some difficult or cannot remember the answers, remember to look more closely at that area during your revision.

1. In a federal criminal trial for sexual assault, the prosecution seeks to introduce evidence that the defendant committed a similar, uncharged sexual assault five years prior. Under the Federal Rules of Evidence, this evidence is:
   1. Inadmissible character evidence under FRE 404(b).
   2. Admissible under FRE 413 to show the defendant's propensity to commit sexual assault.
   3. Admissible only if the prior act resulted in a conviction.
   4. Inadmissible unless the defendant first offers evidence of his good character.
2. FRE 414 allows for the admission of evidence of a defendant's prior commission of child molestation offenses in a criminal case involving child molestation. This evidence can be used to prove:
   1. Motive or identity only.
   2. Propensity to commit child molestation only.
   3. Any matter to which it is relevant, including propensity.
   4. Only if the prior act is substantially similar to the charged offense.
3. A plaintiff brings a civil suit against a defendant for battery based on an alleged sexual assault. The plaintiff seeks to introduce evidence that the defendant committed a similar sexual assault against another person two years ago. This evidence is:
   1. Generally inadmissible under FRE 404.
   2. Admissible under FRE 415 for any relevant purpose, including propensity.
   3. Admissible only if the defendant testifies and puts his character in issue.
   4. Admissible only to show absence of mistake.

Introduction

The baseline rule in the Federal Rules of Evidence is that character cannot be used to show conduct on a particular occasion. FRE 404(a) bars evidence of a person’s character offered to prove that the person acted “in accordance with” that character trait. FRE 404(b) separately bars evidence of other crimes, wrongs, or acts when offered solely to prove a person’s propensity to act in a particular way.

In most contexts, prior bad acts are admissible only for non-propensity purposes—motive, intent, absence of mistake, identity, and similar theories—never simply to show that the defendant is the kind of person who would commit the charged offense. Sexual assault and child molestation cases are different. Congress enacted FRE 413, 414, and 415 to create explicit, controversial exceptions that permit prior sexual misconduct to be admitted as direct propensity evidence.

Key Term: Propensity Evidence
Evidence offered to show that because a person acted in a particular way on other occasions, they were more likely to have acted in the same way on the occasion in dispute.

Key Term: Prior Sexual Misconduct Evidence
Evidence that a party (usually a criminal defendant) committed other sexual assaults or child molestation offenses; under FRE 413–415 this can be admitted, in defined cases, for any relevant matter including propensity.

These rules are tested regularly on the MBE. To apply them correctly, you must identify the type of case (criminal or civil), the nature of the charge or claim (sexual assault or child molestation versus some other crime or tort), and whether the evidence concerns the defendant/party or a third person. Only then can you decide whether FRE 413–415 apply or whether the analysis reverts to FRE 404(b) and ordinary character rules.

FEDERAL RULES OF EVIDENCE 413–415

FRE 413–415 represent deliberate departures from the usual ban on propensity evidence. Each rule applies in a specific class of cases and allows evidence that the defendant or a party committed “any other offense” of sexual assault or child molestation. That evidence may be considered for “its bearing on any matter to which it is relevant,” explicitly including character and propensity.

Key Term: Sexual Assault (Rule 413)
For FRE 413, “sexual assault” includes a range of federal and state offenses involving contact, or attempted contact, of a sexual nature without consent, including attempts or conspiracies and certain offenses involving minors.

Key Term: Child Molestation (Rule 414)
For FRE 414, “child molestation” generally includes sexual acts or contact with a child under 14 (or under the age specified in the rule), attempts or conspiracies to engage in such conduct, and comparable state or federal offenses.

The definitions in the rules are broad; for MBE purposes, any prior offense that clearly involves non-consensual sexual contact (or contact with a minor) will qualify.

FRE 413: Evidence of Similar Crimes in Sexual Assault Cases

Rule 413 applies in a criminal case in which the defendant is accused of an offense of sexual assault.

• Who is the target of the rule? Only the criminal defendant. Evidence that a victim or witness committed prior sexual assaults is not governed by FRE 413; it must be evaluated under FRE 404 and FRE 412.
• Admissibility: Evidence that the defendant committed any other offense(s) of sexual assault is admissible and may be considered for its bearing on any matter to which it is relevant. That includes:
  • Propensity (“once a sexual assaulter, more likely to be one again”).
  • Identity, modus operandi, opportunity, intent, lack of mistake, and similar non-propensity purposes.
• Similarity requirement: The rule does not use the word “similar,” but the prior act must qualify as an “offense of sexual assault” as defined in the rule. On the MBE, prior completed or attempted sexual assaults will satisfy this.
• Timing/Conviction: The prior offense need not have resulted in a conviction and can be uncharged or even previously acquitted, as long as there is sufficient evidence to permit a jury finding that the defendant committed the act.
  • Under FRE 104(b), the judge admits the evidence if a reasonable jury could find, by a preponderance of the evidence, that the prior assault occurred.
• Disclosure: The prosecutor must:
  • Disclose the evidence, including witnesses’ statements or a summary of expected testimony;
  • Do so at least 15 days before trial, or later if the court allows for good cause.

Key Term: Conditional Relevance
Under FRE 104(b), some evidence is admitted on the condition that the jury finds a preliminary fact (such as whether the prior act occurred) by a preponderance of the evidence.

Scope of “Sexual Assault” for FRE 413

Rule 413’s definition of “sexual assault” is broader than just “rape”:

• Any conduct involving non-consensual sexual contact or penetration.
• Attempts, solicitations, or conspiracies to commit such offenses.
• Certain offenses involving minors that are sexual in nature.

On an exam, do not get bogged down in fine statutory details. If both the charged offense and the prior act clearly involve non-consensual sexual contact or contact with a minor, Rule 413’s definition will virtually always be satisfied.

FRE 414: Evidence of Similar Crimes in Child Molestation Cases

Rule 414 mirrors Rule 413 but applies to criminal cases in which the defendant is accused of an offense of child molestation.

• Admissibility: Evidence that the defendant committed any other offense(s) of child molestation is admissible and may be considered for its bearing on any matter to which it is relevant, including propensity.
• Who is the “child”? The rule defines child by age (under 14 in the federal rule). The MBE will usually make the child’s age clear.
• Timing/Conviction: As with FRE 413:
  • No conviction is required.
  • Prior acts can be remote in time, though remoteness may reduce probative value for FRE 403 purposes.
• Disclosure: The same 15‑day notice requirement applies.

Scope of “Child Molestation” for FRE 414

For exam purposes, treat the following as child molestation under FRE 414:

• Sexual touching or penetration of a child under the specified age.
• Attempts or conspiracies to engage in such conduct.
• Certain offenses involving child pornography or sexual exploitation of a child.

If the charged offense is sexual conduct with a child, and the prior acts are sexual misconduct with other children, FRE 414 will apply.

FRE 415: Evidence of Similar Acts in Civil Cases Concerning Sexual Assault or Child Molestation

Rule 415 extends the principles of Rules 413 and 414 to civil cases:

• Scope: Applies in a civil case in which a claim for relief is based on a party’s alleged commission of sexual assault or child molestation.
  • This includes intentional tort suits (e.g., battery, IIED) and other civil claims where sexual assault or child molestation is an element or central allegation.
• Who must be the “party”? The prior acts must be those of a party to the civil case (normally the defendant). Prior misconduct of nonparties is not covered by Rule 415 and must be analyzed under FRE 404(b).
• Admissibility: Evidence of the party’s commission of any other offense(s) of sexual assault or child molestation is admissible and may be considered for its bearing on any matter to which it is relevant, including propensity.
• Disclosure: The proponent must give notice at least 15 days before trial (or later for good cause), similar to Rules 413 and 414.

Interplay with FRE 403

Although Congress favored admitting prior sexual misconduct, FRE 413–415 do not override FRE 403. The judge must still exclude the evidence if its probative value is substantially outweighed by dangers such as unfair prejudice, confusion, or waste of time.

Key Term: Rule 403 Balancing
The court’s authority to exclude relevant evidence if its probative value is substantially outweighed by the danger of unfair prejudice, confusion, misleading the jury, undue delay, or cumulative proof.

Courts often consider factors such as:

• The similarity between the charged offense and the prior act.
• Temporal proximity: how long ago the prior act occurred.
• Frequency of the prior acts (one prior incident versus a pattern).
• The need for the evidence (strength of other proof).
• Reliability of the evidence (e.g., conviction versus uncharged conduct).
• Whether the details are particularly inflammatory compared to the charged conduct.

On the MBE, once you conclude that FRE 413, 414, or 415 applies, the evidence is presumptively admissible subject only to a genuine 403 problem. Very old, loosely supported, or highly inflammatory prior acts are where the exam expects you to invoke FRE 403.

Key Term: Limited Purpose Instruction
Under FRE 105, when evidence is admissible for one purpose but not for another, the court, on request, must instruct the jury to consider the evidence only for the permissible purpose.

Even when prior sexual misconduct is admissible for propensity, it may also be admitted for non-propensity purposes. A limiting instruction can be used to cabin how the jury uses the evidence, or to make clear that it may not be used against other parties or for unrelated issues.

Procedural and Evidentiary Issues

FRE 413–415 do not override other evidentiary rules. Key points:

• Hearsay: The rules do not create a hearsay exception. The prior misconduct usually comes in through live testimony by the prior victim or other witnesses with first-hand knowledge. Out-of-court statements about prior assaults must fit a hearsay exception (e.g., excited utterance, prior consistent statement).
• Standard of proof for prior acts: The judge applies the FRE 104(b) conditional relevance standard. If there is enough evidence for a reasonable jury to find, by a preponderance, that the prior act occurred, the judge admits the evidence and the jury decides whether the act actually happened and what weight to give it.
• Scope of proof: Both testimonial and documentary evidence may be used (e.g., certified convictions, police reports—if not hearsay-barred—medical records, etc.), subject to the usual rules on authentication and hearsay.

Interaction with Other Character and Sexual Misconduct Rules

The special rules coexist with, rather than replace, the general character rules.

• FRE 404(a) and (b): When FRE 413–415 apply, they override the 404(a)/(b) prohibition on propensity use, but only for qualifying sexual assault or child molestation cases.
  • If the case is not a sexual-assault or child-molestation case (e.g., robbery, fraud), FRE 413–415 do not apply and prior sexual misconduct is treated like any other prior bad act under FRE 404(b).
  • If the evidence concerns a third person (e.g., a witness’s prior sexual assault), FRE 413–415 do not apply; you must analyze under FRE 404.
• FRE 412 (Rape Shield): FRE 412 protects alleged victims by limiting evidence of their sexual behavior or predisposition.

Key Term: Rape Shield Rule (FRE 412)
A rule that generally bars evidence of an alleged victim’s other sexual behavior or sexual predisposition in sexual misconduct cases, subject to narrow exceptions.

• FRE 413–415 focus on the defendant’s or party’s prior sexual misconduct, not the victim’s. They do not permit back-door attacks on the victim that would otherwise be barred by FRE 412.
• In civil sexual assault cases, both FRE 412 and FRE 415 may apply. Evidence about the victim’s sexual behavior is restricted by 412, while evidence of the defendant’s prior sexual assaults is governed by 415 and 403.

Worked Example 1.1

Defendant is charged with the sexual assault of Victim 1. The prosecution seeks to introduce testimony from Victim 2, who will state that Defendant sexually assaulted her in a similar manner three years earlier. Defendant was never charged or convicted for the assault on Victim 2. Is Victim 2's testimony likely admissible?

Answer:
Yes, likely admissible under FRE 413. The current case is a federal criminal prosecution for sexual assault. FRE 413 permits evidence that the defendant committed another sexual assault for any relevant purpose, including propensity. A prior conviction is not required; the rule covers evidence of the commission of the offense. The prosecution must provide timely Rule 413 notice. The judge will still conduct FRE 403 balancing, but given the similarity and relatively recent timing, the probative value is substantial and the danger of unfair prejudice is unlikely to substantially outweigh it.

Worked Example 1.2

Plaintiff sues Defendant in federal court for damages resulting from an alleged incident of child molestation that occurred last year. Plaintiff wishes to introduce evidence that Defendant was convicted 10 years ago for child molestation involving a different victim. Is this evidence admissible?

Answer:
Yes, likely admissible under FRE 415. This is a civil case based on alleged child molestation, and Defendant is a party. FRE 415 allows evidence of Defendant's prior commission of child molestation, including convictions, for any relevant purpose, including propensity. The 10‑year gap may reduce probative value but does not automatically bar admission; it is considered in FRE 403 balancing. The fact of conviction enhances reliability. Plaintiff must provide the Rule 415 notice.

Worked Example 1.3

Defendant is on trial in federal court for armed robbery. The prosecution offers evidence that Defendant sexually assaulted a co-worker four years ago, arguing that the assault shows Defendant’s general lawlessness and willingness to harm others. There is no allegation of sexual conduct in the robbery. Is the evidence admissible?

Answer:
No. FRE 413 and 414 do not apply because the current case is not a sexual assault or child molestation prosecution. In a non-sexual case, prior sexual misconduct is treated like any other bad act under FRE 404(b). Here, the only articulated purpose is general propensity to commit violent crimes, which is improper. The evidence is not admissible to show that Defendant is a “bad person” likely to commit robbery.

Worked Example 1.4

In a federal criminal prosecution for child molestation, the defense seeks to introduce evidence that another adult male (not on trial) previously molested the same child victim. The defense argues that this shows the child is mistaken about the identity of the perpetrator. FRE 414 is cited. Is FRE 414 the correct rule?

Answer:
No. FRE 414 applies only to prior child molestation offenses of the defendant. Evidence of a third party’s molestation is not governed by FRE 414; it must be analyzed under FRE 404(b) and ordinary relevance principles. The defense may argue that the third party’s prior abuse is admissible to show an alternative source of the child’s knowledge or injuries, or to support a mistaken-identity theory, subject to FRE 403 and possibly FRE 412. But FRE 414 is not the basis for admission.

Worked Example 1.5

In a federal civil action for battery based on an alleged sexual assault by an employee, Plaintiff sues both the employee and the employer-corporation, alleging negligent hiring and supervision. Plaintiff offers evidence that the employee sexually assaulted two other individuals years before, and also offers evidence that another manager at the corporation sexually assaulted coworkers in the past. Which evidence can be admitted under FRE 415?

Answer:
Only the evidence of the employee’s prior sexual assaults is governed by FRE 415, because the employee is a party against whom a sexual-assault-based claim is asserted. FRE 415 allows Plaintiff to offer the employee’s prior acts to show propensity and other relevant matters, subject to notice and FRE 403. The manager’s prior assaults are not prior acts of a “party” within the meaning of Rule 415. Evidence of the manager’s misconduct might be admissible under FRE 404(b) to show the employer’s notice, pattern of lax supervision, or negligent hiring, again subject to FRE 403, but not under FRE 415.

Exam Warning

Do not confuse the specific rules under FRE 413–415 with the general character evidence rules under FRE 404. FRE 404(a) prohibits using character evidence to prove propensity, and FRE 404(b) prohibits using prior acts for propensity, permitting them only for non-propensity purposes. FRE 413–415 create explicit exceptions for prior sexual misconduct in defined types of cases, specifically allowing propensity use.

A common MBE trap is to assume that any prior sexual misconduct by anyone in a sex-related case automatically falls under FRE 413–415. Always ask:

• Is this a criminal sexual assault case (413) or criminal child molestation case (414)?
• Or is it a civil case based on sexual assault or child molestation (415)?
• Is the prior act attributed to the criminal defendant or a civil party?
• Is the evidence otherwise subject to hearsay or other evidentiary limitations?

If the answer to any of these questions is no, the analysis likely belongs under FRE 404 and the general rules instead.

Key Point Checklist

This article has covered the following key knowledge points:

• The general rule (FRE 404) prohibits character and prior-bad-act evidence when offered solely to show propensity.
• FRE 413, 414, and 415 create specific exceptions in sexual assault and child molestation cases.
• FRE 413 applies to criminal cases where the defendant is charged with sexual assault; FRE 414 applies to criminal cases where the defendant is charged with child molestation.
• FRE 415 applies to civil cases based on a party’s alleged sexual assault or child molestation.
• Under FRE 413–415, evidence of prior commissions of sexual assault or child molestation is admissible for any relevant purpose, including propensity.
• The prior act need not have resulted in a charge or conviction, but there must be sufficient evidence for a jury to find that it occurred.
• These rules apply only to prior acts of the criminal defendant (413–414) or of a civil party (415); they do not cover prior acts of nonparties or victims.
• Parties seeking to introduce such evidence must comply with notice requirements (typically at least 15 days before trial).
• Evidence admitted under FRE 413–415 remains subject to FRE 403 balancing, and courts weigh similarity, timing, frequency, reliability, and need.
• FRE 413–415 coexist with FRE 404(b), FRE 412, and the hearsay rules; they do not create a hearsay exception or override rape-shield protections for victims.
• Conditional relevance under FRE 104(b) and limiting instructions under FRE 105 remain important tools when admitting prior sexual misconduct evidence.

Key Terms and Concepts

• Propensity Evidence
• Prior Sexual Misconduct Evidence
• Sexual Assault (Rule 413)
• Child Molestation (Rule 414)
• Rule 403 Balancing
• Limited Purpose Instruction
• Conditional Relevance
• Rape Shield Rule (FRE 412)