By Jim Melwert

HATFIELD, PA (CBS) — A Hatfield man is facing charges, accused of shooting a man after stepping into a domestic dispute at a party he was hosting at his Orvilla Road home.

Derrick Cosby, 43, is charged with voluntary manslaughter in the July 22 shooting death of 31-year-old Jeremy Chasteen.

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Cosby called 911 that night to report the shooting. The call is quoted in charging documents, with Cosby telling the dispatcher he shot a man in what he calls a domestic violence case, adding, “He was beating his wife and I had no choice.”

The documents say, according to a police interview with Cosby, he was hosting a party when Chasteen started arguing with his wife. Cosby says at two different times, Chasteen hit his wife with a closed fist.

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As other guests were trying to block Chasteen from his wife, Cosby says he pulled a gun and shot him once in the head.

The documents say Cosby never called police, and also never warned Chasteen before he shot him.

Cosby’s lawyer, Ed Galang, issued the following statement in response to the charges:

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“Derrick Cosby is a Navy veteran that has never been in trouble with the law. On the night in question, he was protecting his home and the people in it from a physically imposing, intoxicated individual who was violently wreaking havoc to the people there. He believed that the shooting was justified. Immediately after the shooting, he called 911, remained at the scene, and cooperated with law enforcement. We look forward to the day when all of the facts are revealed behind this tragic event.”