Best ways to keep room mates out of my alcohol?

We escalated to me physically locking any alcohol in my trunk, but they just borrow my car keys at night. I’d be perfectly happy to share, but they’ve got serious problems and any amount of alcohol in them makes me consider a restraining order. They’re almost tolerable to live with when on the straight and narrow. No I don’t have a better living situation around the corner, so focus on the question in the title.

They’re generally too stupid to manage basic personal affairs, but I’ve seen them gain a 3-digit IQ and some Mission Impossible skillsets when there’s an obstacle to drinking. I expect any kind of key will eventually be found when I’m at work. I know how to solve common combination bike locks, I figured that out as a kid for fun. Combination code locks are probably going to be lifted or recorded somehow. Means of bypassing fingerprint scanners are well documented. Any kind of deterrent in the alcohol itself is asking for trouble, they’ll probably drink enough of it for legal trouble or severe illness.

There doesn’t seem to be a market for asshole-proof mini fridges?