A grand jury has declined to bring charges against White Plains police in the shooting of a 68-year-old former Marine at his apartment last year.
The grand jury's decision was announced Thursday by Westchester County District Attorney Janet DiFiore.
"After due deliberation on the evidence presented in this matter, the grand jury found that there was no reasonable cause to vote an indictment," she said.
An attorney for the Chamberlain family said the family will seek a federal investigation.
Raw: Cops Break Down Retired Marine's Door
On Nov. 19, 2011, police were dispatched to the Winbrook Houses public housing project to aid Kenneth Chamberlain, a chronically ill heart patient.
Chamberlain apparently had accidentally triggered his medical alert pendant, and when the responding officers banged on his door, he told them he was OK and refused to let them in.
But then Chamberlain and the police became engaged in an hour-long standoff, and the officers eventually forced open the door, fearing someone else inside was in danger, according to police.
Audio: Chamberlain, White Plains Police
The man's family contends that police then used a Taser on Chamberlain for no reason, then shot him with a bean bag gun before firing two fatal shots.
“My father was murdered by the same people that were supposed to come and help him,” Kenneth Chamberlain Jr. said last month.
Police have said the elder Chamberlain had a knife.
The medical alert company’s voice box in the room captured the conversation. There is also video of Chamberlain captured by the camera on the officer's stun gun.
DiFiore said one officer at the scene, who was not identified, uttered a racial epithet from outside Chamberlain's ground-floor apartment in an effort to distract him from officers inside the building. She said the police department assured her it would review the use of the epithet, as well as its policies on the use of force regarding emotionally disturbed individuals. She said uttering the epithet was not deemed criminal.
"The use of a racial epithet in any context is offensive to the dignity of all of us," she said, adding that when it is used by a police officer "it's intolerable."
The grand jury heard audio and saw video from the case, and heard testimony from 42 witnesses, the DA said. Some 100 exhibits were reviewed, including ballistics and photos from the scene, and the officers involved were among those who testified.
The White Plains police union said the officer's actions were "necessary and justified" and said it was grateful for the grand jury's investigation.
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