CHICAGO (AP) — A Cook County jury has convicted the third and final defendant in the 2010 killing of off-duty Chicago police Officer Thomas Wortham IV.

The jury deliberated for about three hours Monday before convicting 24-year-old Marcus Floyd, who faces mandatory life in prison when sentenced. Jurors found that although Floyd did not pull the trigger, he was legally responsible for Wortham’s killing because he joined his cousin in attempting to rob the off-duty officer.

Officer Thomas Wortham

Chicago Police Officer Thomas Wortham was shot and killed on May 19, 2010. (Credit: Chicago Police Department)

Defense attorney David McMahon tried to lay the entire blame on the cousin for Wortham’s slaying.

Brian Floyd was fatally shot by the police officer’s father, a retired police sergeant, who responded to the shooting outside his home.

Twenty-five-year-old Paris McGee and 34-year-old Toyious Taylor were convicted last year of first-degree murder in the officer’s death.

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