One day after the prosecutor decided not to press charges against a former Seattle police officer in a deadly shooting, a local law expert is questioning that decision. Ian Birk shot and killed woodcarver John T. Williams last August. But King County Prosecutor Dan Satterberg said he can't charge Birk because of a law written 25 years ago that protects officers who use deadly force. 

 But Mary Fan, a University of Washington professor and former federal prosecutor, says Satterberg is not bound by state law and could have charged Birk if he wanted to.

 "You could argue, 'Look, a jury should decide.' File the charges and a jury should decide," she said. "It's a judgment call. It's a close judgement call, and I don't envy the prosecutors judgement call."

 But Fan says it all comes down to the moments right before Birk pulled the trigger -- "looking at Officer Birk's behavior and the way he acted on that film and his tone of voice."