James Peters has been involved in six fatal shootings in the past 10 years while a police officer.
John Loxas was shot and killed while standing in his doorway and holding his 7-month-old grandson.
The American Civil Liberties Union said in a lawsuit filed Monday that the city of Scottsdale "had no business" allowing a police officer with a history of fatal shootings to carry a gun before he shot and killed a man holding a 7-month-old child in February.
John Loxas, 50, died after he was shot by Officer James Peters outside Loxas' home as he held his grandson. The boy was unharmed.
The ACLU filed the wrongful death lawsuit against the city of Scottsdale on behalf of Loxas' daughter, Alexanderia Loxas, and his father, John Loxas, Sr.
"My father was my best friend, Alexanderia Loxas, 23, said Monday during a news conference after the lawsuit was filed. Alexanderia Loxas is the mother of the now 14-month-old child, Neo, held by John Loxas when he was shot.
"I felt safe knowing I had him in our lives because he was always there to protect us, and now he's gone forever," Alexandria Loxas said.
Peters had been involved in five previous fatal shootings over the past decade. He was also involved in two other shootings. Attorneys allege Peters shot the unarmed Loxas Feb. 14 in the forehead with a high-powered rifle, killing him instantly.
"There may well be no other police officer in the country who has been involved in more fatal shooting incidents over this time period," said attorney John Loevy of Loevy & Lovey. "Our lawsuit alleges that the Department had no business trusting him with a gun after he had killed so many other Scottsdale residents."
The lawsuit also names Scottsdale Police Chief Alan Rodbell, claiming he failed to implement adequate accountability policies for his officers.
The incident started when neighbors of Loxas called 911 to report he had threatened them with a gun.
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