Addendum: At the same thread, Donald Willis argues the wallet at the scene belonged to Scroggins:
"DPD Sgt. Kenneth Croy: 'There was a report that a cab driver had picked up Tippit's gun and had left, presumably. They don't know whether he was the one that had shot Tippit...' (v12p202). Certainly, if Scoggins was, at first, wrongly suspected of being the shooter, the police would have wanted to see his wallet."
And on it goes, and always will.