Did we really need one more celebrity sex scandal? Like it or not, that’s what we’re getting with the latest revelation from Letterman. Blackmailed for sleeping with staffers over the years, Letterman refused to cave and decided to go public with his announcement about the whole sordid thing. He turned the shakedown into brilliant late night theater and grabbed the last laugh.

Or did he? Some pundits have said “who cares,” arguing that he was single at the time and these women were consenting adults. But what’s been lost in the whole milieu is that these were all staffers who worked directly under Letterman’s supervision and control!

As I wrote in my book Sexual Harassment: A Reference Handbook, most organizations frown on these relationships on the theory that it creates a conflict of interest for someone to be dating or having sex with someone they supervise. Even if those women allegedly consented, what about third parties who knew about the affairs and claim sexual favoritism because they didn’t get the special assignments and promotions that the women who did have sex with Letterman may have received? These third parties may have claims against Letterman, the network or Letterman’s production company.

And then there’s that troublesome word “consensual.” There’s countless situations where male bosses have assumed that someone was consenting to have sex with them and then later, that same woman came back to claim that they only had sex because they feared losing their job. In fact, the first case to hit the United States Supreme Court on sexual harassment, Meritor Savings Bank v. Vinson, hinged on just such a claim. Mechelle Vinson alleged that — even though during her four years at the bank she’d had sex with her supervisor 40-50 times — she only did so to keep her job. The Supremes bought her argument.

The court opined that Vinson’s consent to the behavior did not relieve the employer of liability. The issue is not the “voluntariness” of Vinson’s behavior, the court found, but whether her conduct indicates that the behavior was unwelcome.

And those troublesome “third parties”? Consider one of the first cases of “paramour preference,” Broderick v. Ruder, decided by the Federal District Court in Washington D.C. in 1988. The plaintiff, a staff attorney at the Securities and Exchange Commission, alleged that several supervisors were involved in sexual relationships with secretaries and a staff attorney and consequently, rewarded them with promotions, cash, and other job benefits. Broderick also alleged isolated instances of harassment directed at her. (In one, a drunken supervisor untied her top and kissed her at an office party.) The court found that a hostile environment was created, even though all of the relationships were entirely consensual. The judge emphasized that the sexual activity in the office was widespread and that it formed the basis for decisions on the terms and conditions of employment. When the plaintiff made it clear that she would not participate, the quality of her work assignments changed.

Letterman rewarded the woman in the center of the tangled love triangle (she also had an affair with the alleged blackmailer), Stephanie Birkitt, his assistant and former lover, with a recurring on-air starring role. Despite the fact that she lacked charm and on-air humor, Letterman also footed the bill for her to attend law school, as his company did for several former staffers. Did men or other women who didn’t have affairs with Letterman resent these perks? Most likely, but only time will tell if any of them turned jealous enough to find an attorney and slap Letterman with a lawsuit.

It’s too early to know what will happen to Letterman. One other former intern, Holly Hester, said she had wanted to marry Letterman but that he broke it off because of their age disparity. Birkitt was immature enough to scrawl confessions in her diary, keeping the kind of record that plaintiff’s attorneys love. One of these women could still come out of the proverbial woodwork to claim that they didn’t really mean yes when they said yes, but only did so to keep their job.

When I teach classes on these issues I always advise managers that they need to avoid these kinds of liaisons. Even if it’s not expressly a violation of your organization’s policy, there’s too great a chance that you’ll be snared by some communication snafu — you thought that your advances were welcome when she thought she had no choice — or that third parties will resent the appearance of favoritism.

Of course, I’m well aware that love happens. And often, love happens at work. According to some studies, over 40% of workers had had an affair with someone they work with. But if you’re a supervisor, it’s just a very dangerous thing to do. If you start dating someone you supervise, do what it takes to change the reporting lines so that he or she doesn’t report directly to you. If there’s no chance that you can do that, I always advise that the classy thing to do is for one of you to leave.

There’s a reason for all those old, crude but wise adages, such as not “fishing off your own pier.”