In the early morning hours of Nov. 25, 2006, Sean Bell, a 23-year-old New York City man due to be married later that day, walked out of a Queens strip club, climbed into a gray Nissan Altima with two friends who had been celebrating with him – and died in a hail of 50 bullets fired by a group of five police officers.

The shooting shocked the city and brought back memories of the deaths in other high-profile police shootings – in particular, the death of Amadou Diallo, an African peddler killed after police fired 41 shots at him in 1999. Both men were black and both were unarmed, although in both cases the officers appeared to have believed the suspect had a gun. While the death of Mr. Bell did not prompt the same levels of rage and protest as the Diallo case, it prompted unsettling questions about the changes in police procedures adopted in recent years, and about whether black men remained unfairly singled out for aggressive police action.

On March 16, 2007, a Queens grand jury voted to indict three detectives in the case, charging the two who had fired the bulk of the shots,Detective Michael Oliver and Detective Gescard F. Isnora, with first-degree and second-degree manslaughter, and the third, Detective Marc Cooper, with reckless endangerment.

The three pleaded not guilty, and in the days before the trial began on Feb. 25, 2008, defense lawyers made clear that they were going to concentrate on potential justification for the first two shots fired by Detectives Oliver and Isnora. In particular, they were expected to focus on evidence that Mr. Bell was intoxicated and on a statement by one of Mr. Bell’s companion that there had been talk outside the nightclub that someone had a gun. The officers have said they followed Mr. Bell and his companions in the belief that they were going to retrieve a gun following a dispute outside the club.— Feb. 25, 2008