## Facts

- A police officer’s handgun was stolen from the officer’s vehicle and later used by others in robberies; Bahman Habibi was not involved in the theft or robberies.
- Law enforcement searched Habibi’s home and found the stolen handgun hidden in a secret compartment.
- The government argued Habibi, a heroin user and trafficker, obtained the gun through relationships with heroin customers and concealed it due to fear of prosecution tied to his drug activity and the gun’s use in robberies.
- At trial, the government introduced evidence that heroin customers frequented Habibi’s home to use heroin he supplied, supporting an inference that they trusted him enough to leave the gun with him.
- DNA testing did not detect Habibi’s DNA on the firearm; an FBI agent testified, based on investigative experience, that objects may be handled without leaving recoverable DNA.

## Issues

1. Whether the district court abused its discretion under Federal Rule of Evidence 404(b) by admitting evidence of Habibi’s heroin use and trafficking to prove knowing possession of the stolen firearm.
2. Whether the district court abused its discretion by allowing an FBI agent to testify as a lay witness about the significance of a negative DNA result, rather than requiring expert testimony under Rule 702.
3. Whether the district court erred by refusing to give a “transitory possession” theory-of-defense instruction.

## Decision

- The First Circuit affirmed the conviction for possession of a stolen firearm under 18 U.S.C. § 922(j).
- The heroin-related evidence was properly admitted because it had non-propensity relevance to knowledge and motive and helped explain how the firearm came to be hidden in Habibi’s home; the Rule 403 balance was not abused.
- The FBI agent’s testimony about the limits of DNA recovery was permissible lay opinion grounded in personal investigative experience.
- The district court properly denied a “transitory possession” instruction because the record lacked evidence supporting brief, incidental possession, given the firearm’s concealment in a secret hiding place.

## Legal Principles

- Rule 404(b) permits other-acts evidence when it is relevant for a non-propensity purpose (“special relevance”), including explaining relationships, motive, knowledge, or how charged conduct occurred, subject to Rule 403.
- Rule 403 permits exclusion only when unfair prejudice substantially outweighs probative value; appellate review is deferential to the trial court’s balancing.
- Rule 701 allows lay opinion based on a witness’s personal knowledge and experience; testimony does not become expert testimony merely because it touches on forensic evidence if it is not presented as scientific or technical analysis.
- A defendant is entitled to a requested theory-of-defense instruction only if the record contains sufficient evidence to support the theory and the instruction is otherwise legally proper and not adequately covered by the charge.

## Conclusion

The First Circuit upheld Habibi’s § 922(j) conviction, ruling that drug-relationship evidence was admissible to show how and why he knowingly possessed and concealed the stolen gun, the FBI agent’s DNA-related explanation qualified as lay testimony, and no evidentiary foundation required a transitory-possession instruction.


United States v. Habibi, 783 F.3d 1 (1st Cir. 2015)