New York state laws make it comparatively easier for parents who smoke marijuana to be brought up on charges of child neglect. In fact, amounts of marijuana that wouldn't even warrant a misdemeanor charge can be used as evidence of neglect. In extreme cases, this could be used to remove a child from her home.
It comes as no suprise that black and Hispanic parents have a disproportionalely higher number of neglect charges due to pot. While this is obviously a thorny issue, it's likely there's some bullshit to be found here.
For more, check out this piece in the Times.