United States v. Pereira, 848 F.3d 17

Background

Pereira, a Newark Airport employee, was convicted for conspiring to possess and distribute cocaine and for aiding and abetting such possession based principally on testimony from two cooperating witnesses (Torres and Olmo).
Torres and Olmo, both guilty pleas and key government witnesses, placed Pereira as a close associate in baggage-handling operations that smuggled drugs and proceeds via American Airlines flights.
Physical evidence tying Pereira to the conspiracy was minimal: a scrap of stationery with his first name/phone and an unusually short trip to Puerto Rico.
On cross-examination Pereira denied involvement; the prosecutor repeatedly asked whether Pereira thought Torres and Olmo had "made up" testimony or were "setting him up," effectively asking him to label them liars.
The district judge often overruled objections and in some instances rephrased or directly put the improper question to Pereira. No curative instruction was given.
The First Circuit vacated the conviction and remanded for a new trial, finding the repeated improper questions (and judicial participation) were not harmless given the thin non-witness evidence and the case’s reliance on witness credibility.

Issues

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether prosecutor may ask a defendant whether government witnesses "made up" testimony or "set up" the defendant (i.e., to comment on other witnesses' veracity)	Such questions were permissible to highlight direct contradictions and were harmless because the jury could see the conflicts	Pereira argued such "were-they-lying" questions are improper—they invade the jury's province, force the defendant to accuse others of lying, and violate Rule 608(a); here they undermined his right to a fair test of credibility	Questions asking a witness to comment on another witness's truthfulness are improper; the prosecutor’s repeated use (sets 3–8) was misconduct and, coupled with judicial reinforcement, required a new trial
Whether defense objections sufficiently preserved the issue for appeal	Govt: many objections were for speculation and did not expressly invoke the rule prohibiting veracity questions, so some errors were unpreserved	Pereira argued counsel repeatedly objected (speculation/improper) and the context made the ground for objection obvious	The court held objections preserved the issue for question sets 3–8 (some earlier sets were treated differently); several objections were explicit and contextualized enough to preserve review
Whether the errors were harmless or required a new trial	Govt: errors were harmless because testimony was directly contradictory and there was other evidence; cited cases where similar questioning was found harmless	Pereira: errors were deliberate, repeated, uncurtailed, and critical because the government's case depended almost entirely on the cooperating witnesses' credibility	The court applied harmless-error analysis and concluded the misconduct was severe, cumulative, and not harmless given weak non-witness evidence and the judge’s participation; conviction vacated and new trial ordered

Key Cases Cited

United States v. Sullivan, 85 F.3d 743 (1st Cir. 1996) (prosecutor should not ask one witness to declare another witness a liar)
United States v. Thiongo, 344 F.3d 55 (1st Cir. 2003) (credibility judgments are for the jury, not witnesses)
United States v. Akitoye, 923 F.2d 221 (1st Cir. 1991) (improper to ask a witness whether another witness lied)
United States v. Schmitz, 634 F.3d 1247 (11th Cir. 2011) (collecting authorities and explaining Rule 608(a) limits and risks of "were-they-lying" questions)
United States v. DeSimone, 699 F.3d 113 (1st Cir. 2012) (distinguishing between asking if another witness was "wrong" or "mistaken"—permissible—and whether they lied—improper)
United States v. Geston, 299 F.3d 1130 (9th Cir. 2002) (reversal where credibility was central and prosecutor asked witnesses if government witnesses were lying)
United States v. Combs, 379 F.3d 564 (9th Cir. 2004) (forcing defendant to call witness a liar is reversible error, especially when coupled with judicial participation)
United States v. Fernandez, 145 F.3d 59 (1st Cir. 1998) (improper questioning may be harmless when other strong, untainted evidence exists)