NEW ORLEANS, Louisiana — Five New Orleans police officers on trial in the shooting deaths of civilians during Hurricane Katrina were portrayed Tuesday in closing arguments as criminals or heroes amid the chaos of disaster.

"It was unreasonable for these officers to fire even one shot," said Assistant US Attorney Theodore Carter, who reminded jurors of video footage that showed they unleashed "54 seconds of gunfire."

The trial, which began five weeks ago, focuses on an incident on September 4, 2005, as two families whose homes were devastated by Katrina's flood waters were crossing New Orleans' Danziger Bridge.

In what prosecutors have described as a "hail of gunfire," two people were killed, both African Americans, and four were wounded.

Ronald Madison, a 40-year-old mentally challenged man described by family members as gentle and loving, was shot several times in the back and died at the scene.

James Brissette, a high school student who friends said was nerdy and studious, also died on the bridge.

The case has put on display two radically different narratives not just of the incident on the bridge, but the overall actions of police in the days after Hurricane Katrina wreaked havoc in the area.

The prosecution has said that officers felt that the law did not apply to them.

The cover-up allegedly started on the bridge immediately after the shootings, when officers discovered they had killed unarmed civilians in cold blood, and involved the collusion of several superior officers, secret meetings, invented witnesses, and manufactured evidence.

Arguing that the officers stuck together to shape their stories, Carter said, "in another situation, that's admirable. But here it's criminal."

The defense has offered a full-throated advocacy of the officers, portraying their clients as heroes who rescued people and "fought bad guys" in a chaotic and lawless city at a time when many of their coworkers had evacuated.

"These are the life and death decisions we call upon officers to make every day," declared Paul Fleming, one the defense attorneys.

Fleming, who represents former officer Robert Faulcon, accused the government of overreaching in their pursuit of these officers, abusing the grand jury process and threatening witnesses with what he called "a pattern of harassment and intimidation heaped upon anyone who said something they didn't like."

Kenneth Bowen, Robert Gisevius, Anthony Villavaso, and Faulcon, the officers involved in the shooting, could receive life sentences if convicted of civil rights violations.

Sergeant Arthur Kaufman, who was not on the bridge, is charged only in the conspiracy and could receive a maximum of 120 years.

Focus now turns to the jury, which will begin deliberating Wednesday on the 25 charges faced by the officers, after receiving final jury instructions from US District Judge Kurt Engelhardt.