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ALBUQUERQUE, New Mexico (CNN) -- Albuquerque police shot a homeless man in the back and killed him, and it was all caught on gruesome detail in a police video.
It is just one more in a long line of police killings that has the city's Police Department on the verge of federal oversight.
James Boyd, a mentally disturbed man who friends say was attempting to camp out in the foothills above Albuquerque one night in March because city homeless shelters had closed, was holding two small camping knives. Officers negotiated with him for five hours, eventually winning agreement from Boyd to leave the makeshift -- and illegal -- campsite.
Then a police stun grenade went off, Boyd, 38, turned his back and three shots were fired.
Police video shows Boyd on his stomach on the ground, wheezing for breath as officers sic a dog on his legs and fire bean bag rounds at him.
He was already mortally wounded. An autopsy on Boyd found he was shot in the back. The medical examiner ruled the death a homicide.
The horrific encounter, routinely recorded as part of police protocol, is now a key part of an ongoing drama in New Mexico's largest city -- a series of protests against the police and city officials. Federal officials are close to a deal that would have them supervising the Albuquerque Police Department.
Records show that 26 people have been killed by city police in Albuquerque since 2010, a per capita rate of officer-involved deaths higher than New York City and Chicago. Forty people have been wounded by police over the same period of time. So far, the city has paid out $30 million in settlements and officials acknowledge that amount will grow.
In a report written before Boyd's shooting, the U.S. Department of Justice blamed the Police Department for poor training and said "we find that the department engages in a pattern or practice of using excessive force during the course of arrests and other detentions in violation of the Fourth Amendment."
Boyd's death has been added to the list of questionable killings. In April 2011, a young Albuquerque man -- whose parents had contacted police because he had mental health issues -- was killed in his own backyard by two plainclothes police.
The officers had come to the home of Christopher Torres on an arrest warrant issued the month before. They said he was armed and shot him in the back as they wrestled on the ground.
Torres' parents, Stephen and Renatta Torres, say he was holding a broomstick, which he laid down when police approached. They sued police, and a judge awarded them $6 million in a civil judgment, saying the police testimony was "not credible."
The Albuquerque district attorney, Kari Brandenburg, cleared the two officers in the Torres killing. She has cleared every other police officer involved in a killing during her last 13 years in office.
Police Chief Gordon Eden has been on the job for only about three months. Initially, he called Boyd's shooting "justified" but tells CNN that he spoke "prematurely, and I shouldn't have."
Eden says he is "holding people to a higher degree of culpability," but he is also facing Justice Department oversight.