The American Civil Liberties Union filed the complaint Monday in federal court in Boston against the U.S. Department of Health and Human Services.
It claims HHS, which distributes grant money to help trafficking victims, has allowed the U.S. Conference of Catholic Bishops to limit the services its subcontractors provide to female victims.
The ACLU says the bishops' conference is misusing taxpayer money and attempting to impose its religious beliefs on trafficking victims.
A spokeswoman for the bishops' conference said, "We will continue to provide those services in the contract that are consistent with our belief in the life and dignity of the human person."
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