> My take is this: We present to others, and even ourselves, the illusion that there's just one unified "self"; but really inside there are a number of independent motivations within us. In both cases above, I think there was a part of those people who felt guilty and actually did want to be caught and punished.
I have a different take. Assuming his crime is driven by his beliefs/mission, not being found will not further it. Logically you may argue that it would afford him more chances to carry on but given that we assume him to be driven by strong and passionate belief, he would want to be clearly and explicitly recognized for those beliefs and would want those thoughts to take center stage of public opinion. Carrying evidence also is his way of broadcasting the signal that he doesn't care about getting caught since he did the right thing and has nothing to be ashamed of.