NEW ORLEANS (AP) — A fourth former New Orleans police officer pleaded guilty Wednesday to helping cover up deadly police shootings of unarmed residents after Hurricane Katrina, the fifth guilty plea in a Justice Department civil rights probe of the case.Robert Barrios, 29, was charged with conspiring with other officers to provide homicide investigators with false accounts of the shootings that killed two people and wounded four others on the Danziger Bridge less than a week after the August 2005 storm.Three other former officers already have pleaded guilty to participating in a cover-up that included a planted gun and phony witnesses.On the day of the shootings, Barrios was one of several officers driven to the bridge in a rental truck, responding to a report that officers were under fire. On the bridge, Barrios saw another officer fire a handgun at a fleeing juvenile without yelling any warnings, according to a court filing Wednesday.Barrios also saw several civilians, including two females, lying bloody and wounded on a walkway.”He did not see any guns on or near the civilians and did not perceive any threat from them,” the filing says.Even though Barrios didn’t fire any shots on the bridge, he “wanted to back his partner and the other officers” and decided to lie and say he fired his shotgun at civilians one time in self-defense, the filing says.Barrios was one of seven officers charged in state court with murder or attempted murder. The Justice Department opened its probe after a state judge dismissed those charges in 2008.During the federal probe, Barrios and other officers learned that Michael Lohman, a lieutenant who supervised the department’s investigation of the shootings, was retiring. An unidentified sergeant expressed concern Lohman might be cooperating with the FBI and told Barrios that all the officers needed to “stick together,” the filing says.Lohman, former detective Jeffrey Lehrmann and former officer Michael Hunter have pleaded guilty to participating in the cover-up.Barrios faces a maximum sentence of five years in prison after pleading guilty to one count of conspiracy to obstruct justice.Marion David Ryder, a convicted felon who was posing as a law-enforcement officer on the day of the shootings, also pleaded guilty Wednesday to lying to the FBI when he claimed a civilian shot at him near the bridge.In the aftermath of the shootings, a police officer showed Ryder a man in handcuffs and asked if he was somebody he had seen shooting.”It looks like him,” Ryder allegedly responded, even though prosecutors said he hadn’t seen anyone shooting.Ryder, 45, of Opelousas, faces a maximum sentence of 15 years in prison and $500,000 fine. His sentencing is set for Aug. 4.—–Contact The Daily Reveille’s news staff at [email protected]