Paul Johnson was found guilty on Tuesday of first-degree murder in the death of 33-year-old artist Lisa Koziol-Ellis in 2013.
Prosecutors say he beat her and stabbed her with a screwdriver and a knife when she confronted him burglarizing her home. Prosecutors say Johnson then came back to clean the scene. Koziol-Ellis' husband found her body.
Johnson's defense attorneys argued that his half-brother actually killed Koziol-Ellis.
After the verdict Koziol-Ellis' brother-in-law, David Holzinger, said the family has received "justice for Lisa."
Johnson is to be sentenced Aug. 10.