sudden mandatory dress code change

I work in an upscale restaraunt in which our uniform is: black dress pants, white men's dress shirt, black tie, long white apron, and black loafer-type shoes.

We've been informed this week that starting Saturday, Dec. 16th, the WOMEN will wear: black HI-HEELS, black mini-skirt (4 inches above the knee), black tight fitting spandex top, and black pantyhose (preferably fish-net). Men's uniform stays the same.

Is it legal to threaten our jobs if we don't comply?????

HELP!!!!!!!!!!!!

It sounds as if the management is making women wear provocative attire, and that alone may be sex harassment. I doubt that management would want the pickets outside (but then again if it is good publicity...), but my sense is a letter from a lawyer would make management take notice.