Federal prosecutors often attempt to introduce a defendant’s prior conviction or alleged misconduct to influence how the jury views the current charge. Federal Rule of Evidence 404(b) limits this tactic. The government cannot use prior acts merely to suggest that the defendant has a criminal character and that the defendant probably committed the charged offense.
If the government is seeking to use a prior conviction or other alleged misconduct against you, contact federal criminal defense attorney Michael J. Petro to discuss whether the evidence can be excluded before trial.
What Does Federal Rule 404(b) Prohibit?
Federal Rule of Evidence 404(b) generally prohibits evidence of another crime, wrong, or act when it is offered to prove a person’s character and show that the person acted in accordance with that character on a particular occasion.
In practical terms, the prosecution cannot argue:
• The defendant committed a similar offense before.
• The defendant therefore has a criminal disposition.
• The defendant probably committed the charged offense because of that disposition.
This is the forbidden propensity inference that Rule 404(b) is designed to prevent.
When Can Prior Act Evidence Be Admitted?
Rule 404(b) permits other act evidence when it is relevant to a legitimate issue other than criminal propensity. The rule identifies several possible purposes, including:
• Motive.
• Opportunity.
• Intent.
• Preparation.
• Plan.
• Knowledge.
• Identity.
• Absence of mistake.
• Lack of accident.
This list does not automatically make the evidence admissible. The prosecution cannot simply label prior misconduct as evidence of “knowledge” or “intent” and end the analysis.
The government must explain why the evidence is relevant to a genuinely disputed issue and identify a chain of reasoning that does not depend on the conclusion that the defendant has a criminal character.
The Government Must Provide Written Notice
In a criminal case, Rule 404(b)(3) requires prosecutors to provide reasonable notice of other act evidence they intend to offer at trial.
The notice must:
• Be provided in writing before trial.
• Identify the permitted purpose for which the prosecutor intends to offer the evidence.
• Explain the reasoning supporting that purpose.
A court may excuse advance notice for good cause, but the government should not be permitted to surprise the defense with highly prejudicial evidence that could have been disclosed before trial.
Defense counsel should examine whether the notice is timely and sufficiently specific. A vague statement that the evidence proves intent, knowledge, or motive may not adequately explain the government’s actual theory of admissibility.
The Government Needs a Propensity-Free Chain of Reasoning
The Seventh Circuit addressed this requirement in its en banc decision in United States v. Gomez.
The court rejected the idea that prosecutors can establish admissibility merely by selecting a purpose from the list contained in Rule 404(b). Instead, the prosecution must demonstrate how the evidence proves the stated purpose without asking the jury to infer guilt from the defendant’s supposed criminal tendencies.
For example, a prior drug conviction does not necessarily prove intent in a later drug prosecution. The proposed inference may amount to nothing more than an argument that the defendant sold drugs before and probably did so again.
That is propensity reasoning, regardless of whether the prosecutor calls it evidence of knowledge or intent.
Rule 403 Provides Additional Protection
Even when other act evidence is relevant for a permissible purpose, the court must still apply Federal Rule of Evidence 403.
Rule 403 permits the exclusion of relevant evidence when its probative value is substantially outweighed by dangers that include:
• Unfair prejudice.
• Confusing the issues.
• Misleading the jury.
• Undue delay.
• Wasting time.
• Needlessly presenting cumulative evidence.
This balancing requirement is especially important under Rule 404(b). Evidence of a prior conviction creates an obvious risk that jurors will punish the defendant for past conduct or assume that a person who committed one offense must have committed another.
The court should consider how strongly the prior act proves a genuinely disputed issue, whether less prejudicial evidence is available, and how likely the jury is to misuse the evidence.
United States v. Chapman
In United States v. Chapman, No. 12-1415, police officers claimed that Marvin Chapman carried a bag into an abandoned Chicago building. Officers recovered heroin and a rifle from the bag.
Chapman was charged with possessing heroin with intent to distribute, possessing a firearm in furtherance of a drug trafficking offense, and possessing a firearm as a felon.
His defense was straightforward. He denied ever possessing the bag. He did not claim that he possessed the heroin without knowing what it was, nor did he argue that the quantity was intended only for personal use.
The district court nevertheless allowed the government to introduce details about Chapman’s prior heroin trafficking conviction. Prosecutors argued that the conviction demonstrated his knowledge of heroin packaging and his intent to distribute the drugs recovered from the bag.
The Seventh Circuit found that the evidence was improperly admitted.
Why the Prior Conviction Was Inadmissible
The prior conviction was relevant only through an impermissible propensity inference. The government’s theory effectively asked the jury to conclude that because Chapman had sold heroin before, he probably intended to sell heroin again.
The court also emphasized that Chapman’s actual defense mattered. He denied possessing the bag altogether. His knowledge of heroin packaging was not a genuine issue in dispute.
Chapman even offered to stipulate that the heroin was packaged in a distribution quantity. That offer further reduced the probative value of his prior drug conviction while leaving its severe prejudicial effect unchanged.
The Seventh Circuit concluded that the evidence should have been excluded under Rules 404(b) and 403.
The Error Required Reversal
The jury convicted Chapman of the drug charge but acquitted him of both firearm charges, even though the heroin and rifle were recovered from the same bag.
The Seventh Circuit found that the inconsistent verdict strongly indicated that the prior drug conviction affected the jury’s decision. The government’s evidence was essentially the same for the drug and firearm charges, but the prior drug conviction applied most directly to the charge on which Chapman was convicted.
The court held that the evidentiary error was not harmless and reversed the conviction.
A Limiting Instruction May Not Cure the Prejudice
Courts sometimes instruct jurors that they may consider prior act evidence only for a limited purpose, such as intent or knowledge, and not as proof of criminal character.
A limiting instruction is important, but it does not automatically eliminate the prejudice. When the prosecution’s theory depends on propensity reasoning, changing the label or giving the jury an instruction does not make the evidence admissible.
Defense counsel should object to both the evidence and any proposed instruction that fails to identify a legitimate, factually supported purpose.
Challenging Rule 404(b) Evidence Before Trial
A strong Rule 404(b) challenge should require the government to answer several questions:
• What precise issue does the evidence supposedly prove?
• Is that issue genuinely disputed?
• What is the complete chain of reasoning supporting admissibility?
• Does any step in that reasoning depend on criminal propensity?
• How similar and how recent is the prior conduct?
• Is less prejudicial evidence available?
• Does the government actually need the evidence?
• Does the danger of unfair prejudice substantially outweigh its probative value?
• Did the government provide timely and adequate written notice?
Defense counsel should ordinarily seek a ruling before the jury hears the evidence. Counsel must also make a clear record of the objection, the government’s asserted purpose, the Rule 403 analysis, and any requested limiting instruction to preserve the issue for appeal.
Michael J. Petro represents people facing federal criminal charges in Tampa and Chicago. If prosecutors are attempting to use prior acts or convictions to prejudice the jury against you, contact federal criminal defense attorney Michael J. Petro.