Can a parent get joint custody or visitation rights if their on probation and

[Just Me]

smoke marijuana? I want full sole custody of my son because his father is unfit, smokes marijuana and is on probation for numerous charges, dwi and possesion. He even tried to get high while the bby is under his care, I do not want him to have custody or even visitation because I do not trust him knowing how he is, he has no education, no job, on probation, smokes weed everyday, can I get sole custody without him having rights? Also im scared hes going to clean his system if we go to court, but trust me he is a pot head and I do not want my son around him please help