It's important to distinguish two issues: (1) whether the currency is usable as currency and (2) whether there are forensic clues enabling law enforcement to id

It's important to distinguish two issues: (1) whether the currency is usable as currency and (2) whether there are forensic clues enabling law enforcement to identify criminals. They're completely separate questions. The value of a dollar bill is the same whether it was used in a crime. But if it has some ink on it, it might provide evidence that the person holding it robbed a bank. The ink doesn't keep the dollar from being usable. It has to be this way. Otherwise money simply gets taken out of circulation, and people participating in the economy have to worry about whether money is money. More: https://www.reddit.com/r/Bitcoin/comments/1qomqt/what_a_landmark_legal_case_from_mid1700s_scotland/ https://www.reddit.com/r/Bitcoin/comments/1qomqt/what_a_land...