...who has served his time and not re-offended, a criminal, or an ex-criminal?
I suppose this brings us round to the rehabilitation debate again, but I guess it comes down to crimes which are a conclusive action, a physical event, that begins and ends, and whether the person who commits that should be viewed continually as a criminal because they once committed that action, and haven't since, or whether they should be viewed as someone who committed a crime, has done their time, and should now be viewed as an ex-criminal, and therefore treated as an everyday person?