"Laws to Control Adultery

Men and women were held to different standards of moral conduct. A woman was considered to behave improperly if she had a sexual relationship with any man other than her husband... A man, on the other hand, whether single or married, was reproached only if his sexual relationship was with the wife of another man. The intent of these moral standards was to ensure that a married woman would become pregnant only by her husband. Thus male sexual infidelity was a moral issue only if it compromised the integrity of another man's family. Wives were expected to tolerate their husbands' "affairs" with slaves, prostitutes, and other "disreputable" women (as did Augustine's patient mother...), but husbands could divorce wives involved in similar behavior and kill the "other" man. The definition of adultery was limited to any sexual infidelity by a married woman or with a married woman.
The emperor Augustus expressed great concern over various social problems in Rome. Many upper-class men chose not to marry; married couples often remained childless. Augustus was disturbed by the decreasing population of native Italians, particularly among the upper class; he also claimed that the was dismayed by the relaxed moral standards of his time and that he wanted to return Rome to the standards of the "good old days." He therefore passed laws (18 B.C., the Julian Laws regulating adultery and marriage; A.D. 9, the Papia-Poppaean Laws regulating marriage) meant to encourage marriage and to discourage adultery. Here are some passages from these laws.

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ADA pp. 113 - 116, 123, 126

'Henceforth no one shall commit adultery or rape knowingly or with malice aforethought." The words of this law apply both to him who abets and to him who commits the crime.

The Julian Law to control adultery punishes no only those who violate the marriages of others. Under the same law, the crime of debauchery is punished, when anyone seduces and violates, even without force, either a virgin or a respectable widow.

By the second section of the las, a father is permitted, if he catches his daughter's seducer, in his own home or in his son-in-law's home,... to kill the adulterer with impunity, even as he may immediately kill his daughter.

A husband is permitted to kill his wife's seducer. ... He is permitted to kill a pimp, actor, gladiator, criminal, freedman or slave who is caught in the act of adultery with his wife in his own home, but not in the home of his father-in-law. ... And he must divorce his wife without delay.

A husband who does not divorce his wife when she has been caught up in adultery, and who allows the adulterer to go unpunished, is himself punished as a pimp.

A husband who makes any profit from the adultery of his wife is flogged.

Women convicted of adultery are punished by confiscation of half of their dowry, and a third of their property, and by exile to an island. The male adulterers are punished by a similar exile to an island (provided they are sent to different islands) and by confiscation of half their property."

Shelton, Jo-Ann. As the Romans Did: a Sourcebook in Roman Social History. New York: Oxford UP, 1998. pg 54. Print.