The Big C is a new series on Showtime about Cathy Jamison (Laura Linney) who has been diagnosed with fatal cancer. Cathy refuses to tell anyone in her life about her diagnosis, but her behavior changes drastically as she copes with the reality that she only has a short time left.

Cathy and her husband Paul (Oliver Platt) live in Minneapolis with their teenage son. Their marriage starts to suffer after Cathy discovers she has cancer. A theme throughout the show is Cathy’s determination to live the rest of her life doing things she enjoys and not worrying about the consequences. This theme is played out when Cathy starts to have an affair with Lenny (Idris Elba), a handyman from the high school where she teaches.

The episode airing on October 11, 2010, “Happy Birthday, Cancer” featured the developing complications of the affair when Paul throws a surprise party for Cathy, just as she is about to leave on a weekend getaway with Lenny. Lenny, unaware that a party is going on, arrives at Cathy’s house to pick her up, and is invited to stay at the party by Paul, who thinks Lenny was just coming by to help Cathy fix something around the house.

Under Minnesota law, adultery is considered a crime for which the adulterer and the paramour may be imprisoned for up to one year and forced to pay a $3,000 fine. However, the only way a prosecution can be made under this law is if the spouse of the adulterer files a complaint. So if Paul discovers Cathy’s affair with Lenny, both Cathy and Lenny could be criminally prosecuted should Paul choose to press charges.

The interesting thing about this Minnesota law is that it is actually gender-based. §609.36 states:

When a married woman has sexual intercourse with a man
other than her husband, whether married or not, both are guilty of adultery and may be sentenced to imprisonment for not more than one year or to payment of a fine of not more than $3,000, or both.

Under §609.36, only married women and their paramours are guilty of the crime of adultery. A married man and his mistress would not be penalized under this law. Another Minnesota statute, §609.34 prohibits fornication, stating “When any man and single woman have sexual intercourse with each other, each is guilty of fornication, which is a misdemeanor.” This statute is textually gender-based, specifying only “single” women.

When §609.34 and §609.36 are read in conjunction, it is illegal in Minnesota for a man to have sex with a single woman or a married woman. Therefore, the only legal option for a man is to sleep with his own wife. So in the application of the laws, they apply to both genders, but they are textually discriminatory against women.

USA Today reported that Minnesota Senator Ellen Anderson suggested the state repeal the laws. The Minnesota Family Council disagreed and argued that the laws should be textually amended to apply to both men and women.

Cathy and most people in Minnesota probably have no idea how antiquated their adultery laws are! In fact, over twenty states still have similar criminal adultery laws in place according to law professor Jonathan Turley. Prosecutions under these laws are rarely made, but they do occur, and can be cited in divorce proceedings, custody disputes, employment cases and even to bar people from serving on juries.