well over in england the law works like this
there is a defence of intoxication which is available if you where so drunk/intoxicated you did not know what you where doing
if you murder someone whilst so intoxicated you do not know what you are doing then no matter how you became intoxicated you cannot be convicted of murder as murder requires the mental element of Intent which obviously cannot be formed due to the intoxication
However if you became intoxicated volunterily then you will be guilty of manslaughter which requires the mental element of intention or recklessness and you are reckless in becoming this intoxicated so thereofore you can be convicted of manslaughter
manslaughter gets a shorter jail sentence compared with murder
If you became intoxicated involunterily I.E. a spiked drink you have a complete defence to any crime and will not go to jail as you cannot have intention to commit the crime and you are not reckless in becoming intoxicated
well, in court with divorce issues, the woman almost always (like 95% of the time) gets custody of children because its a common belief that children need their mother more than their dad, and the dad won't have much chance of getting custody unless the mother is like severely abusing her kids. Even constant drug usage isn't enough to steer court away from mother.