Hi Bob,
well for one this is a rufous morph bird, not a melanistic bird as some may respond. besides the fact that the upper chest and belly are rufous instead of blackish or charcoal colored, the other marks that say it's not a melano are the naturally colored tail, and the fine white barring left intact on much of the dorsal surface.
secondly it also has a racial identity that is hard to pin down on a dark bird. from these photos i would have to say it is either a western race (calurus) or eastern race (borealis) bird, and not the expected Fuertes (fuertesi) race, which is clear-bellied and very pale-tailed. it is also not kriderii or harlani, although because of it's darkness i suppose others might try to call it it harlani. it does not have the posture, tail or habitat selcetion tendency (based on two photos though . . .) of harlani. because the belly band appears so dark i would tend to say it's borealis. but it seems to have a tail more reminiscent of calurus, so between those two, without a skin collection in front of me, i'd have to defer for now . . .
my two cents...
tony g