Fraud can be a state or federal crime, "wire fraud" usually means it is at the federal level because of its use of interstate electronic communications. Mail f

Fraud can be a state or federal crime, "wire fraud" usually means it is at the federal level because of its use of interstate electronic communications. Mail fraud is similar. If you send someone a letter, you're using the US Mail system and thus are involving the federal level making it a federal crime. If you exclusively use a private interstate letter carrier (FedEx, for example), you are still committing mail fraud because the law was amended to cover that.