If you have EVIDENCE of the allegations, and can prove that the motheru2019s behaviors are creating an environment thatu2019s not safe or healthy for the child(ren), then there would be no reason for a Court not to award the father primary physical custody. He may have to share LEGAL custody, though, depending on the state.But, a father bringing such allegations had better have proof. Not just u201cI saw her in a bar drinking one night and I know she was drunku201d. Youu2019d need proof - definitive proof - that she is an alcoholic/drug addict AND it is making her incapable of caring for the child(ren).There are many perfectly functional alcoholics in the world. They go to work, go to school, do their laundry, etc. If you didnu2019t know they NEEDED to drink every night/weekend/whatever, youu2019d never know they are alcoholics. Thatu2019s not going to be enough to deny custody to her. If you can PROVE the child misses school because Momu2019s too drunk to get him/her up and to the school bus in the morning, if you can PROVE that the child doesnu2019t have clean clothes because Momu2019s too drunk to do laundry, if you can PROVE the child isnu2019t being fed or properly supervised due to Momu2019s drinking, then your attorney shouldnu2019t have any problem convincing a judge to award you primary physical custody.