A jury convicted Sir Mario Owens Wednesday, The Denver Post reported. The penalty phase of the trial begins Monday.

The jury found that Owens shot and killed Javad Marshall-Fields and his fiancee, Vivian Wolfe in 2005. Marshall-Fields was scheduled to testify at the trial of a friend of Owens.

Owens is already serving life with no parole for a July 4, 2004, killing in an Aurora, Colo., park.