How seriously do parents have to mess up before the state takes their children away? If you live in New York, not much. The New York Times reports on how trace amounts of marijuana — not enough to even charge a parent with a misdemeanor — could be enough to get the state to seize your children.

The Times tells the story of Penelope Harris, who had a third of an ounce of pot in her apartment last year. The long story short is that her son spent a week in foster care and her niece, who was living with her as a foster child, was placed in another home and not returned to her for more than a year. She had no criminal record and had never before been investigated by child welfare but she had to weather a lengthy child neglect inquiry.

She’s not alone. Hundreds of parents didn’t face criminal charges for small amounts of marijuana but got tangled in child neglect cases, up to and including losing custody of their children:

“I felt like less of a parent, like I had failed my children,” Ms. Harris said. “It tore me up.”

New York City’s child welfare agency said that it was pursuing these cases for appropriate reasons, and that marijuana use by parents could often hint at other serious problems in the way they cared for their children.

As states and localities around the country loosen penalties for marijuana, for both recreational and medical uses, they are increasingly grappling with how to handle its presence in homes with children. California, where the medical marijuana movement has flourished, now requires that child welfare officials demonstrate actual harm to a child from marijuana use in order to bring neglect cases, and defense lawyers there say the authorities are now bringing fewer of them.

But in New York, it’s routine for child welfare to take children away from parents who have marijuana. The bureaucrats say that they have good reason for doing this but defense lawyers say that they seize the children, file neglect charges based solely on the marijuana and then search for other issues to bolster their case. The law for neglect does not distinguish between marijuana and other drugs.

And neglect findings can have other repercussions, too:

Neglect findings, while sometimes allowing parents to keep their children, can have serious repercussions. They prohibit parents from taking jobs around children, like driving a school bus or working in day care, or from being foster care parents or adopting. And they make it easier for Family Court judges to later remove children from their homes.

The findings stay on parents’ records with the Statewide Central Register until their youngest child turns 28.

This seems extreme. If a parent’s drug use renders them unfit, that’s one thing. But the trauma of removing a child from his home or orphaning him is not justified by a couple of tokes on a joint.