IT IS ABOUT THE CHILDREN. If he thinks an attorney or judge would rule in his favor, he's mistaken. If there are documented incidents and the children are old enough to tell someone in CPS and/or a child custody evaluator about the situation, they WILL rule in your favor. I JUST went thru this!
If he puts the children in danger - clearly he already has, has shown that he is not responsible w/ them - clearly already has, etc. etc etc., then if I were in your shoes, there is NO WAY I'd do anything other than file for full legal custody and NO visitation until he gets help. Clearly his $$ is spent on alcholo and stuff vs. what's important.......his kids. Garnish his wages if you have to.
Ask yourself..."What kind of role model is he as a father?" "Do I want my children to be around this kind of environment?" "What positive results are there from my kids being around him?"
Depending on your answers...........it will be CLEAR as to the decision you make. If he's not a fit father, REGARDLESS of that fact that he is a biological father, it's NOT productive in any way, shape, or form! You're better off finding someone from church, another family friend, or related man figure for them to spend time with. Find someone or a couple of responsible men who will be willing to guide, nurture, etc. Otherwise, what is the message you are sending? NOT acceptable behavior as a man or father....