They should just chop the finger off, like they (the bad guys) do on TV shows.
All the secure stuff is on my PC's, which use three levels of high-quality encryption.
Yes, if the NSA wanted to know what's on my computer, they could probably crack it in a year or two, but by then, the password to my checking account and a couple of dozen torrented TV shows are probably not my biggest problem!
A dead finger won’t work for the iPhone print reader.