“Two-headed Janus — diprosopic parapagus conjoined twins”

These hypotheticals are additional thought experiments pushing on the law’s assumption that an actor is an individual. Each case considers how the law would treat dicephalic parapagus conjoined twins (like the Hensel twins) as presented in the earlier piece, Half Guilty.

Q: The twins birth a child: who is the mother?

A: Identical monozygotic twins (twins born from the same, divided egg) have the same DNA, although expressed differently. Because of this it can be hard to tell identical twins apart based on DNA. However, identical twins have distinct fingerprints and can be distinguished in this manner. Similarly, conjoined twins are formed through the partial splitting of an egg and have identical DNA. In this case, because they share genitalia and one set of reproductive organs, they are arguably both the mother. Furthermore, a DNA test to determine the mother would prove inclusive as each shares the offspring’s DNA.

Q: The twins become pregnant: what happens if one wants an abortion and wants to carry the fetus to term?

A: In In re Marriage of Witten, a case of frozen embryos, the former wife wanted to fertilize the embryos to make babies. Her former husband waned them destroyed. The court ruled that the embryos were to be kept frozen until an agreement was reached, putting the burden of the upkeep on the embryos on the party who didn’t want them defrosted, the husband. However,  in the case of the twins there is the issue of terminating potential life, beyond that of unfertilized embryos. Likely the court would enjoin an abortion to protect the rights of one twin and the potential life of the fetus. There are major due process concerns here.

Q: The twins want to marry (not each other): do they marry the same man or separate men?

A: These women are arguably two separate persons. Because of their individuality it would make sense to prohibit them from marrying the same man, as bigamy is illegal in all 50 states. However with shared genitalia, their physiology makes the bounds of traditional marriage an issue.  Note that Chang and Eng Bunker married separate women, sisters in fact, and sired nearly two dozen children between them. They were connected by a band of flesh at the abdomen and did not share genitalia. Obviously, genitalia has less to do with getting a marriage license and more to do with the wedding night.

Q: The twins are driving and are pulled over for speeding: who gets the ticket?

A: Because they have separate consciousnesses and each controls half the body, one twin controls the pedals and the other controls the turn signal while they both control the steering to drive a car. Arguably because it takes two of them to operate the automobile, both should be held liable for any traffic infractions.