Police arrested 57-year-old Leila Mulla, of Astoria, on Monday.
She and her former boyfriend Ronald Dalton Dunnagan, 64, are charged in the murder of Gary Kergan in Baton Rouge in 1984.
Both Mulla and Dunnagan were arrested and then released back then because authorities didn't have concrete proof in the case.
However, police say they recently used new technology to link the former couple to the murder using DNA evidence.
Both suspects are charged with murder, conspiracy and robbery.
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