## Facts

- An undercover officer used three pre-recorded bills to buy two rocks of crack cocaine (0.144 gram) from a seller who produced the drugs from a brown medicine bottle.
- Shortly after the transaction, an arrest team stopped Warren Ricardo Copelin; the undercover officer identified him as the seller.
- Officers recovered the pre-recorded currency from Copelin and associated an additional quantity of cocaine in a brown medicine bottle with him, leading to a second charge.
- At trial, Copelin claimed misidentification and denied selling drugs.
- On cross-examination, Copelin testified broadly that he had never seen drugs in person and had only seen them on television.
- The government impeached that testimony with evidence that Copelin had three positive cocaine drug tests while on pretrial release.
- The trial court admitted the impeachment evidence but did not immediately instruct the jury that it could be used only to assess credibility, not as proof of guilt.
- The jury convicted Copelin of unlawful distribution (the undercover sale) and acquitted him of possession with intent to distribute (the bottle quantity).
- At sentencing, the judge nevertheless included the bottle quantity when calculating the Guidelines base offense level.

## Issues

1. Whether evidence of Copelin’s positive cocaine drug tests while on pretrial release was admissible to impeach his sweeping testimony that he had never seen drugs in person.
2. Whether the trial court’s failure to give an immediate limiting instruction restricting the jury’s use of the drug-test evidence to impeachment constituted plain error requiring reversal.
3. Whether, after an acquittal on the possession-with-intent count, the sentencing court could include the bottle quantity in the Guidelines calculation (not reached).

## Decision

- The court held the drug-test evidence was properly admitted for impeachment because it directly contradicted Copelin’s broad claim of no exposure to drugs.
- The court held the trial court’s failure to give an immediate limiting instruction was plain error, despite the absence of a defense request.
- The court reversed the conviction and remanded for a new trial.
- Because of the reversal, the court did not decide the sentencing issue concerning consideration of the bottle quantity.

## Legal Principles

- When a defendant offers sweeping testimony on direct or cross-examination, the prosecution may impeach that testimony with specific contradictory evidence, even if the evidence reflects prior misconduct, so long as it is offered to show falsity rather than propensity.
- Evidence admitted solely for impeachment that carries a strong risk of unfair prejudice in a closely related prosecution (e.g., drug use evidence in a drug distribution trial) requires a prompt limiting instruction restricting the jury to the permissible purpose.
- A trial court’s omission of an immediate limiting instruction for highly prejudicial impeachment evidence can constitute plain error warranting reversal even without a request or contemporaneous objection.

## Conclusion

The D.C. Circuit ruled that impeachment with Copelin’s positive cocaine tests was permissible to contradict his blanket denial of any in-person exposure to drugs, but the trial court’s failure to immediately instruct the jury on the limited use of that evidence was plain error, requiring reversal and a new trial.


United States v. Copelin, 996 F.2d 379 (D.C. Cir. 1993)