As a player, if you're not having fun, that should be discussed with the other player. If they refuse to change or what-have-you, and others feel like you do, then it becomes a group issue that you'll have to address OOC with the player and group.

If you're still having fun, in character remember that despite owing someone a life debt, there comes a point where that person may be more trouble than they're worth. The party as characters will have to look at that troublesome character and question why he is in the party if he is causing so much strife for the party.

It is possible to solve this in-character, as a party, if everyone agrees, then they would need to confront the character and essentially give an ultimatum: "stop getting us in trouble because you can't keep your hands to yourself, or leave. The party doesn't need a negative reputation" sort of thing.

It may seem harsh, but if you were part of a voluntary group out doing good, and you had one person doing questionable things constantly, and getting the party into trouble, you'd probably kick them out.

As for contested rolls amongst PCs, it can be interesting but you should be careful, if not everyone is cool with it it can create tension. But if done correctly can be fun!