Chambers was fired in 2004 following comments she made to the media about budget shortfalls and the department being understaffed.
In 2004, the National Park Service's deputy director, Don Murphy, said Chambers' comments broke two federal rules, one against public comment about ongoing budget discussions, the other prohibiting lobbying by someone in Chambers' position.
The Interior Department can appeal to federal court.
Chambers, who has been chief of police in Riverdale, Md., said she wants the job. She's owed up to $1 million in back pay and interest.
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