I would suspect they probably paroled Clemmons to WA because he seems to have had family there and AR wanted to get rid of him. Parole offices usually don’t parole somebody without that person having a place to go to, usually a place where he has family.
Allen was paroled about the same time from AR and I read here yesterday that they did know each other in jail; I think Allen and possibly Clemmons became Nation of Islam members in jail.
I’m mystified by this, though, because if Allen was able to drive Clemmons away from the scene, that means he must have been sitting there waiting for him while he was shooting. So to me, that means this was actually an organized conspiracy to kill the police officers. In other words, possibly Clemmons’ family members were accessories after the fact, but it seems to me that Allen must have been in on it.
Allen is being held without bail so let's hope the local authorities are thinking the way you do.