Michael Boysen was released Friday from the Monroe Correctional Facility, where he served a year behind bars for burglary.

CNN: STORY HIGHLIGHTS

After Boysen and his grandparents did not respond to phone calls Saturday, his mother drove over with a key to the house in Renton, near Seattle, and found the couple's bodies.

CNN: STORY HIGHLIGHTS

Boysen and his grandparents' car were missing.

CNN: STORY HIGHLIGHTS