Any information you can get online or over the phone can be forged. (Passwords can be discovered, as can private keys, fingerprints, and the results of genetic

Any information you can get online or over the phone can be forged. (Passwords can be discovered, as can private keys, fingerprints, and the results of genetic tests.) Certain kinds of physical evidence, such as dead skin cells with usable genetic material in them, are to my knowledge effectively impossible to forge, but they can be "accidentally" contaminated beyond usability. Doing things in-person face-to-face is only an improvement if you knew the person before anyone had any incentive to fool you on the person's identity, which is hard; even then, allegiances can be bought, sold, and changed for other reasons. My point is that fixing this issue is out-of-scope for a DVCS. It could, however, be improved a bit.