He has a very extensive DUI record so I don't really have to do a lot of proving that this is a problem for him.
Clearly, with a DUI record, he cannot be trusted to have the kids if he can drive anywhere.
I know this from personal experience. My ex convinced my children to lie to me about his drinking telling them I would never let him see them again. Of course, this was not true, I would just ask that he be supervised, and that meant no drinking for him.
If a drunk has keys and a vehicle, they will drive.
Sorry, I should clarify, every drunk I know, including myself, has driven drunk.
Kids or no kids. I am ashamed and very very lucky.
Don't give him the chance to hurt your children or anyone else.
Beth