DNA trail in LA serial killer case detailed

Lonnie David Franklin Jr. appears for arraignment on multiple charges as the alleged "Grim Sleeper" killer, in Los Angeles Superior Court Thursday, July 8, 2010. (AP Photo/Al Seib, Pool)

July 8, 2010 7:06:47 PM PDT
Old-fashioned undercover work and a slice of pizza delivered the key genetic evidence that helped police nab the man wanted in the decades-long "Grim Sleeper" serial killings case as they put to use a provocative new DNA technique.