According to Florida law, a person cannot be arrested for using force–even deadly force–unless the police first determine that there is probable cause to believe that the force used was unlawful. But what happens in those situations in which the police believe that the force used was unlawful? Are the police allowed to actually state their belief to a jury at the person’s trial? According to Florida’s First District Court of Appeal, the answer is no.

In the case of Bartlett v. State of Florida, Laurie Lynn Bartlett was charged with second-degree murder for killing her boyfriend with a knife. At her trial, the lead detective was allowed to testify that before he arrested Ms. Bartlett, he ruled out the possibility that she stabbed her boyfriend in self-defense. Bartlett was ultimately convicted of manslaughter and sentenced to ten years in prison.

Bartlett appealed her conviction arguing that the detective should not have been allowed to express his belief to the jury that she did not act in self-defense. The appellate court agreed and reversed her conviction. The court stated that although Florida law requires the police to decide whether the force used by someone was unlawful before arresting that person, the police are not allowed to testify about that finding to a jury precisely because the final decision as to whether someone acted in self-defense is to be made by a jury, not by the police. As the court of appeals stated, "[B]y allowing the [prosecutor’s] questions and [the detective’s] detailed answers on a matter within the realm of an ordinary juror’s knowledge and understanding, the trial [judge] improperly invaded the province of the jury as the fact-finder and allowed the detective to serve as a fact-finder . . . by determining that self-defense was not a viable defense for [Bartlett]."

The appellate court went on to state that although the detective was allowed to testify about what he actually saw when he arrived at the scene of the stabbing (for example, a knife, blood, the boyfriend’s wounds), he should not have been allowed to express his opinion about whether Bartlett stabbed her boyfriend in self-defense. That particular issue was for the jury–and the jury alone–to decide.