Gary Ridgway was convicted of an astounding 48 separate murder charges in 2003, the most of any serial killer is U.S. history. Subscribe to Quest TV for more .\rbr\rbr\rbr\rbrMurder Files: The BTK Killer.\rbr\rbr\rbr\rbrMartin Kemp takes us through the shocking story of convicted serial killers Fred and Rose West. They were known to have committed a minimum of 12 murders .