United States v. Alex Alexander, 2014 U.S. App. LEXIS 2137

Alex Alexander was stopped after a traffic encounter in Rockford, IL; officer Honzel smelled marijuana, called a drug dog, and a subsequent search found packaged marijuana, a loaded gun under the front passenger seat, multiple cell phones, scales, and cash. Alexander was alone in the car.
Alexander was charged in federal court with possession with intent to distribute marijuana (21 U.S.C. §841), possession of a firearm in furtherance of a drug crime (18 U.S.C. §924(c)), and being a felon in possession of a firearm (18 U.S.C. §§922(g), 924(e)).
At trial Alexander did not testify; defense theory was lack of knowledge/possession (car not his, no fingerprints/DNA on contraband). Defense challenged Officer Honzel’s credibility (e.g., mistaken street name, no recovered text messages, why wait for a dog if he smelled marijuana).
In rebuttal the prosecutor argued, among other things, that Honzel had “no incentive … to falsely implicate the defendant” and referenced his oath of office, asserting Honzel told the truth. Defense did not object at trial.
Jury convicted Alexander on all counts; district court sentenced him as a career offender to 390 months. On appeal Alexander argued for the first time that the prosecutor impermissibly vouched for Honzel’s credibility.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether prosecutor impermissibly vouched for witness credibility during closing	Prosecutor vouched (expressed belief Honzel had no incentive to lie; invoked officer’s oath), which was improper and requires reversal	Government: remarks were mild, partly invited by defense attacks on credibility, and did not prejudice the verdict given strong evidence	Court: Two remarks crossed the line into improper vouching but were not plain error; conviction affirmed
Whether prosecutor’s “no incentive to lie” statement was improper	That statement implied undisclosed evidence about motive/truthfulness and thus constituted improper vouching	Government: distinguishable/harmless and defense invited response; comment was not outcome-determinative	Court: Statement was improper (analogous to Edwards/Cornett) but harmless in context
Whether referencing officer’s oath was permissible	Such reference bolstered credibility with facts outside the record and is improper	Government: overall argument was fair comment and not seriously prejudicial	Court: Reference to oath was improper but not plain error given trial context and evidence strength
Whether prosecutor’s other rebuttal comments were acceptable	N/A (focus on legitimacy of rebuttal strategy)	Government: comments about why officer would not fabricate a larger story were fair inferences/common-sense argument	Court: Those comments were permissible as reasonable inferences from the record

United States v. Edwards, 581 F.3d 604 (7th Cir. 2009) (prosecutorial expressions of personal belief or implied undisclosed facts about witness credibility constitute improper vouching)
United States v. Cornett, 232 F.3d 570 (7th Cir. 2000) (improper to bolster police credibility by referring to occupational oath or facts outside the record)
Darden v. Wainwright, 477 U.S. 168 (U.S. 1986) (standards for determining when improper prosecutorial argument violates a defendant’s right to a fair trial)
United States v. Wolfe, 701 F.3d 1206 (7th Cir. 2012) (analysis for prosecutorial misconduct when timely objection is made)
United States v. Tucker, 714 F.3d 1006 (7th Cir. 2013) (plain-error standard on unpreserved prosecutorial misconduct)