Depends what your guidelines are. If the guidelines make it impossible for people to comply with on the basis of one of the things that enjoys protection from discrimination under employment law (race, color, religion, ______, or national origin under the Civil Rights Act of 1964, disabilities under the ADA) AND there is no reason why that guideline is necessary to do the job well, I'm reasonably confident that it would be considered a violation of the law and very confident that I would consider such guideline to be wrong. For example, let's say you run a travel agency. You have every right to decide, for example, that your telephone representatives should stand instead of sit, and that should wear no hat while working. But if a person in a wheelchair wants the job, you ought to have to explain why standing is necessary to do the job, as opposed to just a personal preference on your part as the boss. Similarly, if a legitamate part of a person's religious belief is wearing a turban, you ought to have to show that the turban somehow interferes with taking telephone reservations.
