Janet is right. NO rehab can keep him there if he doesn't want to be there. And he may con someone into feeling bad for him and they would let him leave and have a headstart before they told the police. My bro was in jail on 3 felony charges, NONE of them as severe as armed robbery. He was drunk for all of them (2 different occasions) and he did go to rehab. He stayed but realized that several people who were there instead of jail conned the workers into giving them a head start (bail was such that leaving violated the terms and they had to go back to jail). The families that bailed them out and paid $9k for the rehab lost it ALL. One woman actually lost her house - and three days after bail was forfeited her son came back and couldn't figure out why they were so mad at him. didn't they know he couldn't stay then, but if they paid another 9k plus more bail he would stay this time?
Has your son EVER show ANY interest in being clean and sober when he was NOT in trouble? in my opinion it is NOT a real desire to get clean. Granted, my gfgbro did want to get clean after 2 weeks in the county jail, BUT it was the FIRST time he was ever in big trouble. He looked at the other guys there, ones who were on the revolving door system, and did NOT want to get old like that. He also has a VERY unique trait in that he cannot do anything halfway. Doesn't, and never did, know how. So he is the very very rare person who got off the substance the first time through. it has been close to ten years now and he is still going to meetings several tiems a week. You already KNOW your son won't stay. You KNOW he wants out so he has easier access to drugs. If he wants them int here, it is possible to get them.
I think the lawyer is giving advice on what is the best for his client but NOT what a parent would think is best for a difficult child. It would get a lower sentence if he went to rehab. Maybe. It also will cost thousands of dollars. BUT he will be on bail, cannot be held in a lockdown program, and WILL LEAVE AMA. You will be throwing away the bail and the cost of the rehab. You also will have your son out doing heaven knows what. He actually may not be as scared by a 5yr sentence as you think. It is really a 2-3 yr sentence in many places with time off for this and that. Then you have him out and unrepentant.
If your son wants to follow his lawyer's advice, then your son must find the money to pay his bail and rehab. You have spent enough on that. It really takes some addicts far longer than even 5 yrs behind bars to get clean.
Don't wobble. Tell the lawyer he means well but you simply cannot jeopardize your retirement to pay for his bad choices. Then go take a vacation and do something you would enjoy and destress doing. I am serious. yes, you may think he is in jail every minute, but at least you know where he is and that he isn't in some shooting house dead with a needle in his arm because his own bad choice or because he made someone mad or stole from them and they gave him a hot shot to kill him. THAT is what he is facing on the street. So jail/prison at least you know he is getting food daily (at least something, more than on the streets spending every penny on drugs) and has a roof over his head.