That's the question coming up again and again in this week's shooting of "hobby knife"-wielding Jackie Collins. The officer who pulled the trigger, Officer James Walters (who police union president Scott Westerman described this morning as a "very Portland" vegan bike rider) has still not been formally interviewed by investigators.

Public defender and Portland Mental Health Association representative Chris O'Connor pointed out on Think Out Loud this morning, Portland is only one of a few cities were police do not have to give statements to investigators shortly after use of force incidents. As Maxine Bernstein reported in the O, outside police oversight groups recommended in 2003 and again in 2005 that the police do same-day interviews with officers involved in shootings.

The issue is a little tricky. Thanks to the 5th Amendment, no American can be forced to incriminate themselves in court. That means if police officers were forced to explain what happened in shootings, their statement could not be used in court and therefore they could not be criminally prosecuted for any crimes that occurred. As O'Connor explains, "Let's say investigators interviewed an officer after a shooting and the officer says, 'I shot him because I didn’t like him.' That officer's statement would never be valid in court, so he couldn't be tried for murder."

But not forcing officers to quickly give statements can cause serious problems, says O'Connor. "The problem is officers can get together and collude. You get this situation where the ultimate statement is rehearsed. In a system where you don’t have to give a statement immediately, it gives them time to meet with their lawyer and figure out what’s legal."

What O'Connor wants (and the police oversight groups recommended years ago) is for the Portland police union to change its contract to force officers to give statements about shootings within 24 hours. That would lose the chance to prosecute officers for crimes relating to use-of-force, but, says O'Connor, that is a moot point because Portland does not have a habit of prosecuting its officers for crimes involving force. "Let’s face it, they’re not going to prosecute ‘em anyway. There’s almost no situation where the police would criticize an officer in a use of force case, much less prosecute him with a crime. So it’s irrelevant, it’s a moot point. You may wind up with some disciplinary action, but that's the most we can hope for anyway."

With no story straight from the officer involved, information about the shooting has trickled out in not always logical ways, notes O'Connor. "We got a statement from Scott Westerman before the police chief yesterday. Why is the union rep more on top of this than the police chief?"