Located in Illinois. My question is concerning your employer's ability to withold your vacation time if no logistical reason is given. I am a Director for a private college in Illinois, we had just opened a bookstore, it is staffed with trained employees in lieu of the Supervisor just hired and awaiting a notice to former employer.
Problem: My boss, a Senior VP stated that I could not take my vacation as planned eventhough my absence posed no threat to the livelihood of the institution or represented a burden in any way. I think I know the answer to the "Is this reasonable" question.
What latitude do I have to voice this further? I hate to say it, but I am guessing this is legal, but ethical?? Any violation here? Thank you.

Unfortunately for you, you do not have any latitude. Your employer may retain the authority to grant and/or cancel scheduled vacations.