Difficult cases may make bad law, but they can also be a powerful stimulus for thought. A problem may be a candle, as the French writer Paul Valéry put it, but an insurmountable problem is a sun. The Hastings Center, a leading US bioethics think tank, recently posted a legal case that asks ferociously difficult questions about the meaning and scope of marital vows, about sexual activity and incapacitated adults, about the duration of consent and the role of legal rights in intimate relationships. For those with a taste for moral indignation there is rich meat here, but I would urge caution and invite any reader to put, as I have had to, any visceral responses aside and take a longer and quieter look.

The case relates to Mrs Z, a twenty-nine-year old woman who sustained a severe traumatic brain injury in a road traffic accident. She lives with her husband but is unable to speak and is entirely dependent on carers for mobility, personal care and hygiene. She is incontinent and fed by a tube. According to the Hastings Centre case study, “although alert and able to respond to visual, auditory, and tactile stimuli, Mrs Z is clearly unable to participate in even basic decisions.” Recently doctors discovered that she was pregnant. The pregnancy was subsequently terminated but her brothers filed criminal charges accusing her husband of rape, arguing that any form of sexual activity involving someone with such diminished capacity was unlawful. Mr Z argued in defence that his wife would have wanted their intimacy to continue and that the law had no place in the privacy of their bedroom.

There are many questions that the court will have to decide in this case, but they include whether Mrs Z’s lack of capacity to consent to sexual activity overrides Mr Z’s claim to a right to marital privacy and whether their earlier sexual activity is demonstration enough that she would have wanted such intimacy to continue, even where she can only be a passive participant. Depending to an extent on the answer to this question, the court will also need to decide whether she remains in the family home or whether her interests would better be protected by moving her elsewhere.

The Hastings Center has appended three subtle and interesting commentaries from a mix of legal, ethical and, to an extent, disability rights perspectives. I give a flavour of these below, although with slight misgivings as some of the nuance is lost, and I would urge anyone interested to visit the Center’s site – access to the case is free once registered.

Unlike in England and Wales, decision-making on behalf of adults lacking capacity in the US is based upon “substituted judgement,” the requirement to try and identify what the adult would have wanted had she retained capacity.

The difficulty of course is that Mrs Z’s earlier consent to sexual activity gives no clue as to what her views might have been given her current situation. In these circumstances, emphasis shifts to a ‘best interests’ decision, and the court would need to weigh up, as Rebecca Dresser, Professor of Law and Ethics at Washington University in St. Louis put it, “the potential benefits and harms of keeping her at home as well as the potential benefits and harms of placing her in another setting. If her behaviour suggests that she is most content with Mr Z and the children.” Dresser concludes that “the judge could reasonably allow here to remain at home on a trial basis.”

Although marriage is not a defence against a charge of rape, Dresser was doubtful that, in the absence of any obvious physical or psychological harm, prosecutors would pursue such a charge.

When it comes to intimate relationships, the dry language of law with its claims and counter-claims about rights and duties, can seem brutal and intruding. As Carole Levine puts it in her commentary, “the essence of the sexual relationship between loving partners is not a contract, a vow in perpetuity, or a mechanical physiological response but a complex expression of their mutual commitment, love, and passion for each other.”

“Mr Z,” she continues, “does not seem to have accepted his wife’s altered state and what that means for their relationship. He continues to see himself as her lover, when his primary responsibility to her now is to protect her from harm.” Levine remains non-committal as to whether physical intimacy should continue, but suggests that, if Mr Z accepts his obligations to protect his vulnerable wife, and is supported with counselling, the family could remain together at the very least for the sake of the children.

It is of course one thing to establish whether or not a certain action is lawful, quite another to decide whether we would do it ourselves, for the law is not always morally sensitive. To try and answer this question I needed to return to my own unease, to try and identify why I shuddered. Sex has many functions: physical, emotional, reproductive, even, dare I say it, “spiritual,” but it is also always something done in relationship, something that requires a partner. And the difficulty for me is that my wife severely brain damaged would not be my wife as I know her.  And this is where I struggle. Sex is rich in paradox. We make love in so many different moods, for such various purposes – dutifully or wantonly, amicably, comically, drunkenly or even gratefully – but always, in the end, because we decide to. And that mutual decision is crucial. Put law, put talk of rights and obligations to one side. In sex we seek the closest connection with another person, and if we have no idea what they are saying to us, how can we be intimate?

I decided to do a straw poll of one and asked my wife what she thought. She was uninterested in moral complexities. Don’t even think about it, she said. So now at least I know.

Julian Sheather is ethics manager, BMA. The views he expresses in his blog posts are entirely his own.