By Mike Scarcella and Sara Merken WASHINGTON (Reuters) - More than 500 law firms have signed a court brief denouncing Donald Trump's targeting of Perkins Coie and other firms, expressing alarm over the Republican president's intensifying crackdown on the legal profession.

The firms signed a legal brief supporting Perkins Coie, calling the president’s actions a threat “to the rule of law.” The largest firms declined to sign.