If your question states all of the facts, your son should not have much to worry about. Once his sentence on parole is over, he is finished. However, if he has a term of probation following his parole, that failed UA could jeopardize his probation and he might find himself facing revocation proceedings. Since this event has already passed, I would wait and see what course of action the Department of Corrections will take. I would also contact an attorney to discuss your possible options.
Rather than speculate, he should wait for the results. If he failed, there is a chance the parole officer will act. After all, why have a parolee take a drug test for nothing?
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