Ted Olson, one of the attorneys who helped overturn California's Prop 8 before the Supreme Court, has joined LGBT advocates in the fight against North Carolina's HB2.

Olson will file an amicus brief in support of the Justice Department's lawsuit against the state's transphobic law.

"HB2 discriminates against fellow citizens because of who they are,” Olson said in a statement. “This law directly challenges the legitimacy of the identity of transgender persons and then compels them to deny it every time they use a public restroom. There can be no doubt that this is bad for business in North Carolina."

Olson added that the law—which denies trans people basic decency and bars cities from enacting LGBT-rights ordinances—is also bad for business: "It demeans business’s customers, it demoralizes their employees, and it contravenes their values of inclusiveness and respect.

Though he's repeatedly stood up for the rights of LGBT Americans, Olson is not a born progressive: He defended George W. Bush in the Supreme Court case that effectively ended the recount of the 2000 presidential election, and later served as W's solicitor general.

But when he and David Boies came on board to fight Prop 8 at the Supreme Court, he proved that equality is not a right-wing/left-wing issue.

Should HB2 end up at the Supreme Court, we can't think of anyone better than Olson to take it down—he's appeared before the high court a whopping 62 times.