Not according to the article:
Bold emphasis added by me.
To my mind, if they'd consulted and updated the policy first and she'd then refused to comply with the written policy they would have been less open to legal challenge.
I totally agree that what is and isn't acceptable can be a massive grey area which is basically why I think, if you are going to have a policy as an employer you need to nail everything down with as little ambiguity as possible.
When this sort of stuff comes up I try to imagine how an employer would deal with someone coming to work dressed like Lord or Lady Whiteadder
