I certainly can't cite the details of Canon Law, but I don't think the individual doing the confessing is bound by any seal. If it is, I'm in trouble as I've personally apologized to people I've slighted or offended after confessing my sins to a priest.
I just searched for ‘requiring a person to turn himself in for absolution.’ I guess they can urge or recommend you to do it voluntarily but can’t make absolution conditional to turning yourself in to the authorities. I guess the logic is it forces someone to divulge their confession and this would in turn discourage people from seeking confession.
FReegards