Sorry cb. That is a difficult situation. I agree, stop the detective work. He will hide whatever he needs where ever he wants.
You may want to kindly mention to him that you are concerned about him taking up drinking. It will ultimately be up to him as to what decisions he makes.
I found that if my wife tried to help me "control" my drinking (and I have asked her to help me), it caused some tension. I finally decided to leave her out of it and seek the support of this community. Maybe suggest he looks at the site. So far it's working for me!!!
Good luck.
KPatrick