New Orleans has reached settlements totalling $US13.3 million ($A18.3 million) in civil rights lawsuits brought against the city for the killings of residents by police in the chaotic aftermath of Hurricane Katrina in 2005.
Mayor Mitch Landrieu said the city reached deals with 17 plaintiffs to settle all claims in the cases that have prompted local police reforms and federal investigation into suspected misconduct by numerous officers.
The settlements included families of those killed on the city's Danziger Bridge in September 2005, where two unarmed people were fatally shot.
"We are here to proclaim from the highest mountaintop that the City of New Orleans, in all of its agony and in all of its joy, can transform itself from a city of violence into a city of peace," the mayor said.
Landrieu held a prayer service with family members and asked for forgiveness ahead of announcing the settlements.
The families have been in litigation for years and their suits alleging misconduct and cover-ups helped to change the narrative of police actions following the hurricane.
The storm led to more than 1,500 deaths in the New Orleans-area.
Mary Howell, a civil rights lawyer who represented families of victims, said the settlement marked a change for the city which typically settles without admitting wrongdoing. She said the apology was deeply appreciated.
"It has been a tortured path to this point," Howell said in an interview.
Those gunned down on the bridge included Ronald Madison, a 40-year-old with the mental development of a six-year-old. He had seven gunshot wounds in his back. James Brissette Jr, 17, was also fatally shot, court documents showed.
Five ex-New Orleans police officers pleaded guilty in April to charges in connection with the killings. Four other people were seriously injured in the bridge incident.
The bridge incident victims, all black and unarmed, were trying to survive the hurricane's wake when a group of officers, believing they were racing to the scene of a police shootout, barrelled toward them in a commandeered truck.
The death of Henry Glover was part of the settlement. A few days after the storm, he was fatally shot by a police officer, who was eventually acquitted. Another officer was convicted of setting Glover's body on fire.
The settlement included the case of Raymond Robair, 48, who local media said was beaten to death by police about a month before Katrina.
