Amber Guyger, 31, is expected in a city courthouse Monday morning, where she will stand trial for the fatal shooting of 26-year-old Botham Jean last year.
The case has attracted intense national scrutiny for its strange circumstances and as one in a chain of shootings of black men by white police officers.
Lawyers for Guyger are likely to argue she fired in self-defense based on the mistaken belief that she was in her own apartment and that Jean, an accountant from the Caribbean island nation of St. Lucia, was a burglar.
The case may hang on whether the jury believes that this was a reasonable mistake, according to legal experts. Twelve jurors and four alternatives were selected to hear the case earlier this month, but their demographics aren’t yet public.
Guyger was off duty but still in uniform when she shot Jean in his home. She told investigators that after a 15-hour shift she parked on the fourth floor of her apartment complex’s garage — rather than the third floor, where she lived — and found the apartment’s door ajar.
Three days after the shooting, Guyger was arrested for manslaughter. She was subsequently fired from the Dallas police department and charged by a grand jury with murder.
The jury will have to decide whether Guyger committed murder, a lesser offense such as manslaughter or criminally negligent homicide, or no crime at all.