If they want to do that, that's fine. They'll probably bite off more than they can chew. With the average person, usually if somebody has some fraudulent intentions, it's for financial gain. They can basically adopt your credit profile. They establish a new identity, not for fraudulent purposes to deceive or steal money or property, but for the process of protecting one's own property.
People have multiple identities for that reason.
Authentication these daays is basically based on something you know, like a password or something you have or an access device or biometrics, and I guess what protects the confidentiality of information now is cryptography. Hacking in my mind is a skill set. People can take that skill and use it in any way that their conscience lets them use it. People can use it to do good things or bad things. But it was honorable back when I was started.