The idea that you arrest someone to serve time in your prison because he broke your laws, and then you cannot send them back because of another law is just mind-blowing.
How so? That's sort of the whole point of law and the government. You may not follow the law, and you may be punished if you don't, but they are always supposed to. You don't forfeit all your rights just because you break the law.
Well, yeah, but this guy gained whatever rights he has in the US just by breaking US law and being kept in prison there. Not only didn't he forfeit rights just by breaking the law - he gained his rights that way! Sounds a tad buggy and something a lawmaker might want to fix to avoid this kind of thing next time.