Did this happen in Rialto or another state? This makes a big difference as to wether or not you should be asking California attorneys or not.
If he is on probation, then he may have some issues for a probation violation. There are really more facts needed in order to be able to answer this question.
If you would like a free consultation, please feel free to contact me.
California Penal Code 12020 (a) states that it is illegal to own, carry, or manufacture brass knuckles. It is also illegal to import, sell, keep for sale, lend or give brass knuckles to another person within California. Those found in violation of penal code 12020 (a) face up to a maximum of 1 year in custody.
As the prior attorney stated, what will happen to your boyfriend is dependent on whether or not he was charged in California and his prior record. You do not indicate if the drug charges were for possession, drug paraphernalia or sales and whether or not he is still on probation. If he is currently on felony probation, a probation violation will be of more concern to him.