If I ever had someone demand this, I would update my account to show my sexual orientation as homosexual, my religion to Islam, and my political views to whatever the opposite of my boss's were. Then if they ever tried to lay me off, or not give me a raise, I would point out that the only useful information they possibly could have gotten from demanding my Facebook account were these protected statuses.
Of the three listed, the only one that is actually protected in the United States is religion. In the vast majority of the United States you can be fired for being gay or a republican. If you work for a labor organization in the United States, you have to be fired for certain political views and organisational memberships (the left-wing variety).
On a federal level yes, but many states (including New York and California) have protection against sexual orientation. I'm surprised to learn that political affiliation is not protected.
I think you've just hit on the legal remedy for this bullshit.
It is illegal for an interviewer to ask about your religion, your race, your age, your political views, your sexual orientation, etc. All of those things are part of the typical facebook profile so asking to even look at someone else's facebook profile for purposes of an interview is a clear violation of the law.
