WHAT would Les Dawson have said? The European Court of Human Rights has held that one may marry one’s mother (actually father)-in-law, thereby removing the remnants of the ban imposed by Henry VIII. The Strasbourg decision results from Article 12 of the Convention on Human Rights that provides a “right to marry and found a family”. Is there anyone left whom one may not wed, let alone not have sex with, nor have children by?

When “L” and “B”, L’s former daughter-in-law, attempted to give notice of marriage at Warrington Register Office, the superintendent registrar must have congratulated himself on a once-in-a-lifetime opportunity to demonstrate his knowledge of the law. The Marriage (Prohibited Degrees of Relationship) Act 1986 had pruned an extensive list of banned “affine” marriages, so much so that during the passage of the Bill, Lord Meston was constrained to ask: “Who are all these people . . . that list which one was tempted to study only during the less gripping moments of school sermons?” So far as parent-in-law nuptials were concerned, Parliament temporised in 1986 by lifting the ban only where both parties are aged over 21 and both “intervening” spouses have died in the interim. In the Warrington case, the balked bride had a child by her previous husband, her present inamorata’s son, thereby potentially adding stepfather status to the groom’s role as grandfather. Despite illustrating Lord Meston’s difficulty in keeping up with the debate on the 1986 Bill, the potential for such confusion did not convince the European judges. While accepting that the part-ban pursued a legitimate aim in protecting the integrity of the family, they pointed out, one, that it did not prevent such relationships from occurring de facto, and, two, that the incapacity can anyway be removed ad hoc by private Act of Parliament. The Warrington Two had already been cohabiting for nine years and the child called L “Dad”. The Department for Constitutional Affairs is considering the judgment, and B and L have nearly £12,000 in damages to put towards a reception.

Are there any remaining couples denied wedlock? The 1986 Act was similarly cagey in dealing with the previous ban on step-parent-child matrimony. Again, each party must be aged over 21, and in addition the stepchild must not have been brought up in the previous family. The policy is therefore to prevent marriage where one party has effectively acted as the other’s parent during childhood. Yet in the Strasbourg case it was held that “since no incest or other criminal law provisions prevented extramarital relationships between parents-in-law and children-in-law, it could not be said that the ban on the marriage (between B and L) prevented B’s child from being exposed to any alleged confusion or emotional security”. So given that step-relatives, once safely adult, are free to have an affair and cohabit, perhaps the new Strasbourg principle will one day apply to them, too.

The “prohibited degrees” of marriage are being reduced to extinction so far as affines are concerned, but consanguine bars are still in place. Although Tom Lehrer sang of Oedipus Rex, “One thing on which you can depend is/ He sure knew who a boy’s best friend is”, one’s parents, siblings, grandchildren and grandparents remain unmarriable. So too do one’s blood aunts, uncles, nieces and nephews, although it has only recently become illegal to cohabit with one or more of the latter lot. This is because the Sexual Offences Act 2003 now renders sex with them incestuous — although preferring the description of “sex with an adult relative” — thereby equating the list of blood relatives whom one may not marry with those with whom one may not cohabit.

The Civil Partnerships Act 2004 has the additional advantage of consolidating pretty much the whole of marriage law. In enumerating the sorts of same-sex pairs who may not register as partners, Schedule 1 mirrors the prohibited degrees for marriage. But unlike their “straight” equivalents the consanguines, and not just the affines, may have legal sex with one another and thereby enter into “unregistered” partnerships. Furthermore a registered partnership may be neither dissolved for adultery nor annulled for non-consummation. It follows that registration, unlike marriage, does not directly confer any sexual entitlement, exclusive or otherwise. No doubt ministers fought shy of concocting the necessary definitions — one for female couples, one for male — and, even 40 years after the decriminalisation of male homosexuality, they balked at the prospect of nullity applicants complaining about not being sodomised.

Professor Barton is a vice-president of the Family Mediators Association

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