@Barry2021,
The guy's an idiot but you still have to live with his mother.
Contact a lawyer and have him or her tell your wife what her son's rights are. Maybe he has some in the car, particularly if he's paid everything or almost everything.
This lawyer may also turn out to be a good choice for the guy's defense. If your stepson has $ then he should be paying for the lawyer. If he doesn't, then IIRC you and your wife have separate accounts. If so, then if she wants to foot the costs (likely in the thousands for a felony), then that's all on her. And she should be looking at stuff like this in the context of retirement.
Anyone with adult children is closer to retirement than not, and an expense in the thousands is not a good thing.
If you're protecting your assets now, fine. But are you protecting them for your retirement years? If you aren't (I am not a financial services expert), check into putting your money into an irrevocable trust.
This situation, forget the guy for a moment, this situation is going to come to a head eventually. Having a decent amount of money for retirement can make an enormous difference in the quality of your life when you're at your most vulnerable.
And in the age of Covid, a better assisted living or nursing home can potentially be the difference between having protection from a fatal disease, or not.