Premise: Gary Leon Ridgway ( born February 18 , 1949 ) is an American serial killer known as the Green River Killer . He was initially convicted of 48 separate murders and later confessed to nearly twice that number . As part of his plea bargain , an additional conviction was added , bringing the total number of convictions to 49 , making him the most prolific American serial killer in history according to confirmed murders . He murdered numerous women and girls in Washington State during the 1980s and 1990s . On November 30 , 2001 , as he was leaving the Kenworth truck factory where he worked in Renton , Washington , he was arrested for the murders of four women whose cases were linked to him through DNA evidence .
Hypothesis: Gary Ridgway is known as a killer.
Label: ENTAILMENT