From SB Nation Website

http://www.sbnation.com/nfl/2013/2/12/3983136/tim-walton-rams-defensive-coordinator

From Detroit's Website

Tim Walton joined the Lions as secondary coach in 2009. Before coming to Detroit, he was the defensive coordinator at the University of Memphis (2008) and had additional responsibilities coaching the safeties. Throughout his 14-year collegiate coaching career, Walton coached 13 players who were eventually drafted into the NFL, including five first round picks (Patriots S Brandon Merriweather, Seahawks CB Kelly Jennings, Giants CB Kenny Phillips, Redskins S LaRon Landry and Cardinals S Antrel Rolle) and four second round picks (S Idrees Bashir, WR/KR Devin Hester, S Michael Stone and CB Corey Webster).

From ESPN.com

http://espn.go.com/nfl/story/_/id/8942328/tim-walton-named-defensive-coordinator-st-louis-rams-sources