Victimless (they're not really, but the victims are diffuse and don't know that the crime is happening) crimes are inherently hard to prosecute. That's because

Victimless (they're not really, but the victims are diffuse and don't know that the crime is happening) crimes are inherently hard to prosecute. That's because the first step in a criminal investigation is usually someone calling the police to report that something has happened. The hard part of prosecuting a mugger or a thief is finding out and then proving who committed the crime - that a crime took place is usually obvious. The hard part of prosecuting "victimless" white-collar crimes is even knowing that anything has happened, that's before having to prove that what happened was illegal and determining exactly who did it.