it sends the message: "if I am ok with chopping off my own finger, then do you think I will be stopped by anything you can throw at me? And if I'm crazy enough to do it, what do you think I will do once I get anywhere near your, or people you love the most, like yourself?"
It's also a bit daft, because not only do they now have your fingerprint, but your DNA and all the other unique identifiers that come with your blood and flesh.
I suspect that it won't be long until they're found, unless they're one of the few people who are totally off the system.