This post has been corrected. It originally said that five current or former New Orleans police officers had been accused of shooting civilians in an incident at the Danziger Bridge after Hurricane Katrina. Four current or former officers were charged in connection with the shootings. A fifth was accused of helping to orchestrate a cover-up.

The landmark trial of several current or former New Orleans police officers accused of shooting unarmed civilians on the Danziger Bridge after Hurricane Katrina culminated today, leaving the final chapter of this pivotal incident in a jury's hands.

ProPublica and our partners at the New Orleans Times-Picayune and PBS "Frontline" have investigated police misconduct in the storm's aftermath as part of the series "Law & Disorder." The shootings on Sept. 4, 2005, at the Danziger Bridge were the most well-known incidents of post-Katrina police violence. About a dozen officers arrived at the bridge after a distress call about a fellow officer under fire. According to prosecutors, the officers began spraying bullets at unarmed civilians, killing two and wounding four more.

A 2008 state case against officers involved in the shootings was tossed out after a judge concluded that prosecutors mishandled grand jury evidence. Federal prosecutors subsequently opened their own investigation into the incident.

In the trial that opened June 29, no one disputed that four officers

—Robert Gisevius, Kenneth Bowen, Anthony Villavaso and Robert Faulcon—had fired at civilians. (See this Times Picayune diagram for the agreed-upon facts.) Instead, the trial focused on whether they used reasonable force and acted willfully and if they conspired to cover their tracks. A fifth defendant, retired homicide Det. Arthur Kaufman, was accused of helping the other officers in a cover-up.

Early in the trial, defense attorney Frank DeSalvo called the prosecution's theory of the case "a fairy tale." In closing arguments today, Assistant U.S. Attorney Theodore Carter said it was the accused officers who had concocted a fairy tale to explain away their actions.

"[Officers] thought they knew that the people on the bridge were criminals. They thought they knew the people on the bridge shot at police. They thought these people who shot at the police had to be taught a lesson," Carter said. "They thought because of Katrina no one was watching. They thought they could do what they wanted to do and there wouldn't be any consequences. It never occurred to them that they were shooting two good families."

Defense attorney Paul Fleming, referring to Sept. 4, 2005, countered in his closing statement: "This is a day like no other. It is a time of disorder, chaos and lawlessness. ... That doesn't mean the rules change, but the perception changes. What is reasonable gets looked at a lot differently." His client, Robert Faulcon, admitted to fatally shooting Ronald Madison, 40, in the back.

As anticipated, the trial unearthed police misconduct and lurid details that were previously unknown. A firearms expert testified that bullets or shotgun pellets from at least three different weapons hit and killed James Brissette, then 17. A forensic pathologist added that a shotgun blast to Brissette's head likely immobilized him before three other shots entered him.

Only one officer on trial testified. Defense attorneys brought in an expert in police psychology to explain how the chaotic conditions after the hurricane could have prompted veteran police officers to shoot unarmed civilians, in the grip of "fight-or-flight syndrome." For three days, the defense tried to poke holes in the testimony of FBI agent William Bezak, suggesting that federal investigators failed to explore whether people besides the officers fired weapons on the bridge.

In his testimony, Bezak stressed that while the investigation by the Orleans Parish district attorney's office concentrated on the actual shootings, his focus was on the cover-up that followed. The feds got Jeffrey Lehrmann, a former NOPD officer sentenced to three years in prison for not reporting a felony, to record a 3-hour chat with Sgt. Robert Gisevius at Lucy's Retired Surfers Bar & Restaurant. The conversation hinted at a conspiracy. Jurors also took a field trip to inspect the bridge firsthand.

They begin deliberations tomorrow.

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