AUGUSTA, Maine (AP) Maine Attorney General Aaron Frey is urging the U.S. Supreme Court to ban discrimination against the hiring of workers based on sexual orientation and gender identity.

A coalition led by Illinois Attorney General Kwame Raoul and New York Attorney General Letitia James is filing the amicus brief in three cases that involve workers being fired based on sexual orientation or gender identity.

More than 200 corporations, including many of America’s best-known companies, are also urging uniform federal rules are needed.

Frey said attorneys general’s argument is “rooted in the fundamental principle of equal treatment” and that discrimination is unacceptable.

Other states are California, Colorado, Connecticut, Delaware, the District of Columbia, Hawaii, Maryland, Massachusetts, Michigan, Minnesota, Nevada, New Jersey, New Mexico, Oregon, Pennsylvania, Rhode Island, Vermont, Virginia, and Washington.