Theft of a credit card is a felony in the fifth degree for each count. See ORC 2913.02 and 2913.71. Misuse of credit cards can be either a misdemeanor or felony depending on the nature of use of the card. See ORC 2913.21. Felony charges carry prison time. If he's turned 18, he's looking at 6 months minimum. He needs an attorney.