“You’re not accused of anything,” the judge told the mother of an infant in family court in Brooklyn last summer.

The woman was the victim of domestic violence. She was in family court because she had told her therapist that her ex-boyfriend beat and slapped her and yanked her dreadlocks out in front of their 9-month-old daughter. The judge issued an order of protection barring him from the home.

But despite the mother’s blamelessness, the judge also pronounced a sort of sentence on her: She and her daughter would receive “announced and unannounced visits” from the city’s child welfare agency, the Administration for Children’s Services, during which investigators could search their apartment, interrogate the mother and physically examine the child for signs of abuse.

Thousands of times a year across New York State, advocates for families say, parents — usually women — who have been abused by their partners are then subjected to surveillance from child welfare authorities.

It is considered child neglect for one parent to abuse the other in the presence of their children. Often, after a victim reports abuse, A.C.S. files a child neglect case against the accused parent and a judge bars that person from the home and grants the agency “supervision” over the parent who was abused.

A lawsuit filed on behalf of the Brooklyn woman in the Appellate Division of State Supreme Court in December seeks to change that. Oral arguments in the case are expected to be heard within a few months.