The Bush administration is challenging a court order requiring it to make housing payments to thousands of families whose homes were damaged by Hurricane Katrina.
US District Judge Richard J. Leon says confusing, often contradictory letters to hurricane victims from the Federal Emergency Management Agency didn't explain why housing funding was cut.
He said that violates the Constitution and ordered the agency to restart the program immediately.
FEMA says it will appeal that ruling.
The government is still under a court order to make housing payments for people displaced by last year's storm. But the Association of Community Organizations for Reform Now says in court documents that FEMA has refused to disclose its plans for restarting the program.
FEMA may ask an appeals court to put the judge's ruling on hold while the appeal plays out.