Jason Griffin is charged with manslaughter, unlawful possession of a firearm and felon in possession of a gun for the deadly shooting.
Investigators say Griffin was at a party in the 300 block of West 23rd Street.
At some point during the party, the victim, now identified as Daniel Barber, put on a bulletproof vest.
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Police say Griffin took out his gun and shot Barber in the chest.
He was killed.
Griffin left the party before returning to talk with police.
His girlfriend told ABC13 he didn't mean to kill his friend. She said Griffin didn't even know his gun was loaded.
"He goes 'shoot me.' Well, he didn't think there was nothing in it, and he did. And the dude went '@##$ that hurt' and then he dropped. And then Jason ripped the vest off of him and tried to help him,'" said Mary Warstler.
Warstler said Griffin was suicidal after the shooting and had to be treated for seizures before he was arrested.
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