The man accused of strangling and robbing his grandparents after they welcomed him home from prison pleaded not guilty Thursday in Seattle to two charges of aggravated murder.
The King County prosecutor has 30 days to decide whether to seek the death penalty but could ask for more time to make a decision.
Michael Chadd Boysen remains jailed without bail.
The 26-year-old is accused of killing 82-year-old Robert Taylor and 80-year-old Norma Taylor after they held a party for him at their Renton home. Their bodies were discovered March 9 by their daughter -- Boysen's mother.
Boysen was arrested March 12 after a 10-hour standoff at Lincoln City, Ore., motel where the manager recognized him from news reports.
Boysen had served time in prison for burglary and robberies.