Less obviously, expectations.
In an interview with NPR’s Shankar Vedantam, Mary-Hunter McDonnell of the Wharton school of business explained the difference between how men and women are judged by their peers for ethical infractions.
Professor McDonnell and her colleagues asked volunteers to recommend a jail sentence for a hospital administrator who filed a false Medicare claim. When the volunteers believed that the administrator was a woman, the average suggested sentence increased by over 60%.
The researchers also analyzed over 500 disciplinary proceedings in 33 states by the American Bar Association. They discovered that women were disbarred more than twice as often for similar types of misconduct.
The assumption here is that, since women are expected to be more ethical, they are punished more severely when they violate ethical standards.
This may be unfair in practice, but in principle is makes perfect sense. Moral people are expected to behave better than immoral people; consequently, we find their moral lapses less tolerable.
Which brings us back to the Clintons.