Arizona is joining 10 other states in a federal lawsuit to challenge President Barack Obama's mandate requiring all public K-12 and postsecondary schools to open boys' and girls' locker rooms and restrooms to students of the opposite sex, based on students' perception of their "gender identify."

The president has threatened to deny federal funding to all schools that object to this decree. The challenge seeks declaratory relief against a number of federal agencies in order to block the implementation of the new mandate.

Without the lawsuit, schools would be forced to implement new policies and procedures to comply with the mandate, said Olabisi Okubadejo, an attorney with Phoenix law firm Ballard Spahr LLP. "If you don't allow a student to use the restroom aligned with their gender identity or use that locker room, it could be a violation for Title IX," she said. "You could potentially lose your federal funding if you don't comply."

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