NEW ORLEANS (AP) — Months before Sgt. Robert Gisevius was charged with plotting to cover up the shootings of unarmed residents on a New Orleans bridge after Hurricane Katrina, he met a former colleague at a bar and shared his suspicion that someone was leaking information to federal investigators.

Gisevius didn’t know that his companion that night, former police detective Jeffrey Lehrmann, was cooperating with the FBI and secretly taping their profanity-laden conversation in November 2009.

“What weak link could sink the ship?” Gisevius asks Lehrmann on the tape, which jurors heard Monday during the federal trial of Gisevius and four other current or former officers. The five defendants are charged in the shootings that killed two people and wounded four others on the Danziger Bridge in September 2005.

In response, Lehrmann mentioned the name of an officer who fired his gun on the bridge but wasn’t accused of killing anybody. Gisevius rejected that suggestion, saying the officer’s lawyer was still “in all our meetings.”

“I don’t think he would sink the whole crew,” added Gisevius, who later speculates that “somebody in homicide” was the leak.

Police are accused of shooting unarmed, wounded residents on the bridge as they responded to an officer’s distress call. Lehrmann and four other New Orleans former officers have pleaded guilty to participating in a cover-up that included a plot to plant a gun, fabricate witnesses and falsify reports to make the shootings appear justified.

FBI Special Agent William Bezak, who narrated portions of the tapes, said Lehrmann was the first officer to cooperate with the federal probe. He already had testified before the grand jury when he met Gisevius at the bar.

On tape, Gisevius speculated that federal investigators were targeting him and six other officers who had been charged in state court with murder or attempted murder charges. After a judge dismissed those charges in 2008, the Justice Department’s civil rights division in Washington opened an investigation.

“You never had a D.C. zealot coming after you who thinks you’re a dirty cop,” he said. “They want a fight, dude? I’m ready to fight.”

Gisevius also said Sgt. Arthur “Archie” Kaufman, now a fellow defendant on trial, “sunk his own ship” by agreeing to talk to federal authorities about the shootings.

Kaufman was assigned to investigate the shootings. On tape, Gisevius expressed hope that Kaufman wasn’t “dumb enough” to leave a “bull—— report” on the shootings stored on his computer, which the FBI searched.

Prosecutors say Kaufman retrieved a gun from his home and turned it in as evidence, claiming it was thrown off the bridge by Lance Madison, whose 40-year-old brother, Ronald, was shot and killed by police.

“If the gun didn’t exist, only two people would know that,” Gisevius said on the tape. “It would be (Sgt. Kenneth) Bowen or it would be Archie, right?”

“Right,” Lehrmann said.

Bowen, Gisevius, Officer Anthony Villavaso and former officer Robert Faulcon are charged in the shootings.

Gisevius later joked about fleeing to a country where he couldn’t be extradited.

“Australia, maybe?” Lehrmann asked.

“They extradite,” Gisevius said.

Also Monday, as the trial entered its fourth week, U.S. District Judge Kurt Engelhardt excused a juror because she is related to the wife of one of the defendants.

Federal prosecutors had asked for the woman to be removed from the 12-person jury. She was replaced by one of four alternates.

Prosecutors said the woman, “due to no wrongdoing on her part,” learned during the trial that she was related to a defendant’s wife.

A court filing Monday by prosecutors doesn’t name the defendant or specify how the juror is related to the officer’s wife.

Copyright 2011 The Associated Press.