v. Monroe, 2020 CO 67

Sheila Monroe stabbed a fellow passenger on a city bus and claimed she acted in self-defense after the victim reached into his pocket.
During closing and rebuttal, the prosecutor repeatedly argued Monroe’s failure to retreat undermined the reasonableness of her belief that deadly force was necessary.
Defense objections were overruled; the trial court instructed the jury that Monroe had no duty to retreat but told jurors they could consider failure to retreat when assessing whether she reasonably believed an imminent use of force was occurring.
The jury convicted Monroe of first-degree assault and attempted first-degree murder; she was sentenced and appealed.
The Colorado Court of Appeals reversed, finding the prosecution’s argument effectively imposed a duty to retreat; the Colorado Supreme Court granted certiorari, held that arguing failure to retreat to undermine self-defense is improper, found the trial court abused its discretion in permitting those arguments, and reversed and remanded for a new trial.

Issue	Plaintiff's Argument (People)	Defendant's Argument (Monroe)	Held
Whether the prosecution may argue that a defendant acted unreasonably in self-defense because she failed to retreat	Failure to retreat is part of the "totality of the circumstances" and is relevant to whether the defendant reasonably believed force was necessary	Colorado’s no-duty-to-retreat rule forbids treating failure to retreat as evidence undermining a self-defense claim	Prosecution may not argue that a defendant acted unreasonably in self-defense because she failed to retreat; such argument is improper
Whether admitting those arguments was an abuse of discretion	The prosecutor clarified there was no legal duty to retreat and only urged jurors to draw inferences about belief and reasonableness	Arguments misstate applicable law and risk imposing a de facto duty to flee, confusing the jury	Trial court abused its discretion by permitting repeated prosecutorial statements that failure to retreat undercut Monroe’s self-defense claim
Whether the error was harmless	The People argued jurors were properly instructed and clarifications cured any error	Monroe argued repeated improper remarks and the trial court’s direction made the error prejudicial	Error was not harmless: repeated improper statements and the court’s allowance created a reasonable probability the error contributed to conviction

Brown v. United States, 256 U.S. 335 (1921) (retreat is not a condition of the right to self-defense)
Cassels v. People, 92 P.3d 951 (Colo. 2004) (only initial aggressors must retreat; no-duty-to-retreat rule explained)
Riley v. People, 266 P.3d 1089 (Colo. 2011) (jury should consider totality of circumstances in assessing reasonableness of defensive force)
Kaufman v. People, 202 P.3d 542 (Colo. 2009) (analysis of self-defense instructions and defendant’s perception of threat)
Martinez v. People, 224 P.3d 1026 (Colo. App. 2009) (contextual discussion distinguishing retreat-related argument used to show initial aggression)
People v. Sepeda, 581 P.2d 723 (Colo. 1978) (prosecutor may not misstate law or tell jury how law should be applied)