A federal judge in California ruled Tuesday that the Trump administration is required to provide mental health services to the thousands of migrant parents and children who were separated at the U.S.-Mexico border, reports the New York Times.

Why it matters: This decision "marks a rare instance of the government being held legally accountable for the mental trauma brought by its policies," writes the Times.

Judge John Kronstadt found that the government can be held responsible for its actions when it places people in dangerous conditions with "deliberate indifference."

Those who've been deported will likely not be eligible for treatment.

The big picture: Carrying out mental health screenings and treatments will be a long and expensive process since thousands of the impacted migrants are spread out across the country.

What's next: Carl Tobias, a law professor at the University of Richmond, told the Times that he "assumes the government will appeal and get the order stayed because it’s brand new. They’ll say the judge got it wrong.”

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