Seventeen-year-old Ryan Anderson pleaded guilty last week to second-degree robbery and was sentenced to three years in a juvenile rehabilitation facility.
The Olympian reports he initially appeared in adult court. The four other defendants in the case, who are 17 to 19 years old, are facing trial as adults in Thurston County Superior Court.
Court papers say Anderson drove the four last January to an apartment parking lot where they intended to rob Daniel Smith of marijuana. Smith was shot and killed, leaving a wife and two young daughters.
Prosecutor Jon Tunheim said several defendants are gang members.