I love David Letterman. His late-night talk show is clearly the best of the bunch, and in my mind, he’s followed along in the footsteps of his mentor, the great late-night king, Johnny Carson.

But as much as I like Letterman and “The Late Show,” the news that he has been, as The New York Times put it, having “sexual affairs with staff members,” made me wonder: What the hell is this guy thinking?

It’s clear to me that David Letterman, highly paid late-night comedian and CBS talk show star, never heard (or conveniently forgot) one of the most basic managerial rules of all—don’t fish off the company pier.

Getting involved with your co-workers (sexually, romantically, or both) is not only terribly foolish, but can also be incredibly dangerous, as Letterman just found out. If you are powerful and highly paid like Letterman, it can open you up to $2 million extortion attempts.

And, although what Letterman was confronted with is extreme, there are numerous and regular examples of powerful executives who are tripped up by romantic entanglements that are just flat inappropriate and stupid.

Although many of the details are sketchy, there’s nothing that says what Letterman did was anything but consensual. One CBS Radio report I heard said Letterman was having sex with female staffers in his office, and as bad as that sounds, it’s still legal for consenting adults to engage in such behavior should they choose to do so.

That’s what catches me up, however. Why would any thinking, rational person—particularly someone of Letterman’s stature—choose to put themselves in a compromising position like that?

“While Letterman seems to be in no immediate risk of losing either his family or his job (ratings from last night’s telecast will likely be stratospheric), his troubles may not be over,” Time magazine says. “Having sex with people who were his employees or whom he managed could leave him, or CBS, open to a sexual-harassment lawsuit. It’s certain the comedian has given the network’s lawyers plenty of reasons to be up at night.”

Bosses getting involved with those who work for them is a trend that’s probably as old as the workplace itself. However, it’s fraught with peril and, in my long experience, is almost never worth the risk.

In fact, if you looked at this as a smart businessperson and examined the risk-reward potential, or the ROI of such a relationship, you probably wouldn’t get involved in such a deal at any level. But, that’s applying rational thinking to something that’s clearly an irrational decision.

Letterman has had a lot of drama and bad stuff to deal with in his life, but this is one that wasn’t foisted upon him; it’s trouble that’s self-inflicted. Even if the foiled extortion attempt turns out to be the worst of it, he’s left his many fans wondering just how someone who seems so smart and snappy on the surface can engage in such foolish (and some would say terribly bad) behavior when the office door is closed?

As someone who makes his living skewering other people and joking about their foibles, Letterman’s now going to become the punch line for a lot of manager and workplace jokes.

Who wants to be that guy? No manager that I know of. Yet Letterman, the guy who has publicly reveled in zinging Bill Clinton, Eliot Spitzer and many others for their sexual high jinks, is now going to become the poster boy for bosses behaving badly. That’s called karma, I believe.

And the jokes and zingers about this have already started. As Time magazine solemnly notes: “Letterman has also probably given truckloads of material to other comedians—or even his own writers. Let’s just say he may come to regret calling his company Worldwide Pants.”

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