NEW ORLEANS — A federal judge today acquitted a police sergeant of a charge he stomped on a dying, mentally disabled man who was gunned down on a New Orleans bridge after Hurricane Katrina, overturning parts of a jury verdict that convicted five current or former officers of civil rights violations.

U.S. District Judge Kurt Engelhardt upheld the majority of the officers’ convictions, but he concluded jurors didn’t hear sufficient evidence to convict Sgt. Kenneth Bowen of stomping on 40-year-old Ronald Madison after another officer shot and fatally wounded the man on the Danziger Bridge in the 2005 storm’s aftermath.

Engelhardt also found insufficient evidence to convict Bowen and three other officers of conspiring to falsely prosecute shooting victim Jose Holmes, who wasn’t arrested or charged with wrongdoing after he was wounded by police.

But the judge left most of the verdict intact and rejected defense attorneys’ bids for a new trial.

U.S. Attorney Jim Letten said his office is reviewing Engelhardt’s ruling and is weighing options, including whether to appeal.

“The majority of the counts and the serious counts are intact, but all the counts are important to us,” he said.

Police shot and killed two people and wounded four others on the bridge less than a week after Katrina’s landfall.

All five of the defendants, including a retired police investigator who wasn’t charged in the shootings, were convicted of engaging in a brazen cover-up that included a planted gun, fabricated witnesses and falsified reports. Jurors convicted them of all 25 counts they faced.

Bowen’s attorney, Frank DeSalvo, said he hopes the ruling will help the officers when they are sentenced by Engelhardt.

“Nobody is going free. How much it helps us at sentencing, only time will tell,” he said. “The more serious counts are still there. You’ve still got two dead people.”

The case was a high-stakes test of the Justice Department’s effort to rid the police department of corruption and brutality. A total of 20 current or former New Orleans police officers were charged last year in a series of federal probes. Most of the cases center on actions during Katrina’s aftermath, which plunged the flooded city into a state of lawlessness and desperation.

The officers convicted of charges stemming from the shootings — Bowen, Sgt. Robert Gisevius, Officer Anthony Villavaso and former officer Robert Faulcon — face possible life prison sentences.

Faulcon was convicted of fatally shooting Madison, but the jury decided his killing didn’t amount to murder. Faulcon, Gisevius, Bowen and Villavaso were convicted in the death of 17-year-old James Brissette. Jurors didn’t have to decide whether Brissette was murdered because they didn’t hold any of the defendants individually responsible for causing his death.