They are legal to keep here. I also just now talked to a guy who works at a reptile store here in Colorado, while I was purchasing a rat. He said that they are illegal to sell, NOT illegal to keep or own. Here is a link explaining the law-
http://www.examiner.com/article/colorado-s-reptile-and-amphibian-wild-catch-regulations

Thanks to the two of you who replied that the Bull is a pituophis catenifer sayi specific species. I suspected this but had some doubt about it, because when doing google image searches of this & the Sonoran gopher some pics looked just like Iggy.
Thanks again for your help in clearing this up!