> If someone shot a person with my gun, I would invoke the fifth amendment, and ask the government to prove who did it beyond a reasonable doubt.

Sounds nice on paper, but unless you have an absolutely airtight alibi that's a great way to end up in jail. Oh, you were alone at home all night? Well, your neighbor is pretty sure they heard you come home unusually late, and a witness saw someone who kinda-sorta looked like you run away from the crime site, and the victim was sorta-kinda involved in your social circles, and there's video of victim bumping into you a few weeks ago in a bar and you reacting in what could be interpreted as an aggressive way - and it is your gun...

Or you could tell them who you loaned the gun to. Your choice.