Allegations that Hollywood mogul Harvey Weinstein sexually abused women for decades spurred a wave of accusations against powerful men in the U.S.

Since The New York Times exposed Weinstein back in October, dozens of men have been accused of so-called sexual misconduct — behavior that ranges from harassing female coworkers and subordinates to rape. The accused include star journalists, actors, politicians, entertainment power players, and, more recently, high-profile chefs, among others.

One group of power players has been largely absent from this list: CEOs of big companies, particularly major, publicly traded corporations. Why do these people seem immune from the post-Weinstein phenomenon, at least thus far?

Employment-law and human-resources experts have a few theories about why, citing the fact that powerful CEOs don’t make the news as frequently as, say, Kevin Spacey, and that they’re often accountable to boards of directors and shareholders.

‘CEOs are pretty institutional players’

It’s notable that one of the most recent public scandals involving a public-company CEO occurred over seven years ago. That’s when Hewlett-Packard ousted Mark Hurd following an inquiry into sexual harassment allegations. (While that investigation couldn’t substantiate a sexual-harassment claim, it did reveal that Hurd had filed inaccurate expense reports. He’s now CEO of tech giant Oracle.)

One possible explanation for why Hurd is one of the only big-time CEOs investigated for alleged sexual misconduct is that sexual predators do not rise to the rank of CEO as often as they achieve high levels in other fields, like politics.

“Everybody is waiting for the other shoe to drop on big companies but I’m not sure that’s going to happen,” says Minna Kotkin, who directs the Brooklyn Law School Employment Law Clinic. “There are always going to be some outliers. But I think by and large CEOs are pretty institutional players.”

Moreover, Kotkin says, CEOs are scrutinized more closely than those in other professions. “I think their time and their days are somehow more regulated. They have too many people watching,” said Kotkin, noting that this is simply a theory that could be incorrect.

‘Very sophisticated policies against sexual harassment’

Big corporations almost always have firm policies against sexual harassment along with regular trainings intended to prevent this kind of behavior, though that’s no guarantee that these practices are 100% effective. Still, just this week, the CEOs of both GM and United Airlines publicly committed to having harassment-free workplaces.

“Bigger companies have very sophisticated policies and practices against sexual harassment, and in the biggest public companies, the CEOs are held accountable for their behavior by the board of directors,” said Peter Cappelli, who directs the Center for Human Resources at the University of Pennsylvania’s Wharton School. “In smaller companies and especially in private companies, they don’t have these policies, and the top people are not held accountable by anyone.”

Of course, sophisticated human-resources departments do not guarantee that victims of sexual harassment will be heard. As The New York Times noted this week, HR departments have an inherent conflict of interest because they work for a company that could be liable over complaints that are brought to them.

Moreover, companies that have large HR departments also tend to have large legal departments — including a couple of lawyers whose sole job is to deal with discrimination or harassment claims, as Kotkin, of Brooklyn Law, pointed out. These lawyers have an interest in preventing sexual harassment but also have an incentive to settle these claims quickly. Since many settlements include non-disclosure agreements, complaints against big-time CEOs may just never end up seeing the light of day.

‘We may unfortunately have a lot more to discover’

Indeed, the day of reckoning for corporate America may be yet to come.

“I don’t see the question as why sexual harassment is not rampant in industry as it is in media or entertainment. I see the question as why women may be less likely to bring complaints in those industries, not whether there is underlying harassment, which I think there most assuredly is,” says L. Camille Hébert, a professor at The Ohio State University’s law school.

Many of the women who have brought complaints regarding sexual misconduct have been celebrities themselves, she noted. Women in other industries might be more vulnerable than those celebrities and therefore less likely to come forward, she said.

The public might also be more interested in hearing about tales of misdeeds involving actors or media personalities like Matt Lauer than CEOs.

“Stars attract the attention of the public and media — they make news, and we know more about them and their industries than say about top executives in chemicals,” says Columbia Business School’s Bruce Kogut. “We may unfortunately have a lot more to discover than we have up to now.”

Erin Fuchs is deputy managing editor at Yahoo Finance.

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