Stained Car Seats Could Be Key to Grim Sleeper Case Investigators also take guns and porn from his home By John Johnson, Newser Staff Posted Jul 16, 2010 9:00 AM CDT 0 comments Comments A July 8 photo of Lonnie David Franklin Jr. at his arraignment. (AP Photo/Al Seib, Pool) (Newser) – Investigators have begun the long slog of trying to make a case against the suspected Grim Sleeper serial killer. Among the items pulled from the Los Angeles home of Lonnie David Franklin Jr.: guns, handcuffs, a cop's notebook, a ski mask, a flier of a missing woman, and porn. But perhaps most significant are car seats, reports the LA Times: Investigators think he raped and shot victims in his vehicle and are testing the fabric of the front passenger seats. “Phase one is over," says one of the lead detectives. "Now it’s on to phase two, learning everything we can about him.” Franklin, 57, is charged with killing 10 women over two decades, but police expect more cases will surface once evidence begins rolling in. Ballistics tests on the guns taken from his residence could be the key to those.