In 1998, the ABC newsmagazine Nightline fretted that the Clinton scandal with Monica Lewinsky would “come down to the question of whether oral sex does or does not constitute adultery.” President Bill Clinton, supposedly, had told Lewinsky that oral sex could not be adultery. He had told Gennifer Flowers the same thing, according to state troopers in Arkansas in 1992. Making this distinction between oral sex and adultery was also part of President Clinton’s legal strategy in his multiple sex scandals. It seemed to many Americans that Bill Clinton had reached a new nadir of political double-speak and lies. But Clinton was not the first philandering spouse to attempt to distinguish oral sex from adultery. Instead he was taking advantage of a legal definition of adultery that emerged from the post-World War II system of fault divorce, which held that only vaginal sex counted as adultery. Under this legal regime, men and women could engage in a range of sex acts, which the courts recognized as sodomy, and still maintain that they had not technically cheated.
Until the 1970s, to get divorced, an innocent spouse had to prove that his or her wife or husband had violated their marriage vows. Judges, not spouses, determined whether a breach met the standard of a set of divorce “grounds” established by state legislatures. In other words, a spouse could successfully fight to stay legally married by denying fault under the prescribed grounds. Some states had loose and flexible grounds for granting divorce—notably Nevada, which allowed for divorce in cases of mental cruelty, separation, insanity, and more. Others had strict grounds such as New York, which allowed divorce only in the case of adultery.
When it came to adultery under the postwar fault divorce legal regime, only extramarital vaginal sex counted as cheating. Every other sex act counted as sodomy or crimes against nature. As one Nebraska judge stated in 1958, “Our statutes classify sodomy under ‘Crimes against nature.’ … The decisions all agree that sodomy is not adultery. All agree that it may constitute cruelty.” This separation of sodomy from adultery enabled husbands who engaged in a range of sex-acts with men or women to claim that they had not committed adultery. Clinton’s rationale fell squarely within this long tradition of only counting vaginal penetration as sex.