Medical examiner testifies in '66 shooting trial

William Barnes (left) was charged Monday, Sept. 3, 2007, with murder following the death of Walter T. Barclay (right), a rookie Philadelphia police officer he shot more than four decades ago, a crime for which he has already served a prison term. ((AP Photo/Philadelphia Police Department, File))

May 19, 2010 10:15:16 AM PDT
A former medical examiner testifying about the death of a paralyzed Philadelphia police officer is being asked whether he's biased in favor of law enforcement.