Neither one of them rings any bells, but I doubt that either of them has been listed on the Public Domain Heroes wiki yet--I suspect they come from the pre-superhero Centaur comics. It's tempting to imagine that the former thief is Barton Stone, the Catman, but they never did get around to saying exactly what the crime he served 20 years for was (altho it was made pretty clear that he hadn't actually committed it), and he only had two adventures, which were exotic only because of his fashion sense...
On the subject of looking for Centaur characters, I'd still love to see some of the Mastermind's adventures, as well as the Western heroes Headless Horseman, Nighthawk, and Ghost Rider.
-comicsnorth