Download this photo. As difficult as it might be, study it until you could recognize the person face-to-face. When you're on the streets and a cop stops you, look carefully. Is it the same person? If so, be very very very very very careful! Who knows if he'll kill again...
Report when you see him, and where, so we can keep track of him. Can we find his address? Perhaps his neighborhood can be flyered with this photo so the people there can know who lives nearby. A little community pressure is a non-violent and often very effective approach.
This post is NOT encouraging anyone to hurt Sery. The cops would use it as an excuse to go ballistic, and they'd do it in N. or NE Portland, where folks already have enough headaches from the police. This post is here to hold the police accountable. If they fuck up like this, they need to have it widely publicized. No Special Protection for police! They are our employees, and if one of them kills one of us, we need to know who it is!