Note: The term 'cousin marriage' is used here to mean marriage between first cousins, unless indicated otherwise. The term is sometimes used more broadly to include marriages between second cousins.
A second reading of a bill to ban first cousin marriage is expected in July, continuing a debate which has simmered on the backburner of political discourse for some time. Public discourse has been limited, quite possibly because many people do not realise such marriages are legal. However, a recent YouGov poll has found 77% of Britons support a ban. Support for a ban is slightly higher in younger age groups and in women, but it is interesting to note that every age group, gender and political affiliation showed a majority support for the ban. The biggest differential was ethnicity, but even in communities with the lowest support for a ban (Pakistani & Bangladeshi communities), still less than half said the practice should be legal.
Given this indication of clear public support for a ban, the success of the bill might be taken for granted. However, the mechanisms of a 'ban' are not straightforward. This is not an article arguing for or against a ban, but for a more nuanced discourse about what, exactly, is meant by a ban and whether that will address the concerns around the practice of cousin marriage.
Historically speaking, cousin marriage has been common practice in England since the 16th Century, when Henry VII decided his fourth wife would be his second wife's cousin, and he made such marriages completely legal; no one has un-legalised it since then. The practice was socially acceptable into the 21st Century. It was not that the genetic risks of cousin marriage were entirely unknown, but in small communities, confined by geographic location and social class, people had fewer options. It is not clear when the shift to a general taboo happened, but at some point, we reached a consensus that there was no need to marry snaggle-toothed cousin Lesley when there are apps full of people to swipe right on. The practice has been continued by discrete communities in Britain only.
Those who advocate for a ban on cousin marriage generally point to three things:
1. Children of these unions have a higher risk of birth defects. This risk is compounded by multiple generations of cousin marriage. See the infamous Hapsburg jaw for an extreme example of this.
2. Cousin marriage is associated with other practices, like forced marriage, where young people, usually young women, are pressured to marry within the family, often to secure family unity or a visa for their spouse;
3. Sociological concerns that inter-family marriage fosters tribalism. The theory is (broadly) this: when a family marries within itself, it incentivised to look to its own fortunes. Families that expect their offspring to consistently marry into other families have greater investment in the prosperity of the wider society.
The question is: would banning cousin marriage address any of these things?
Void, voidable or non-marriage
We must ask ourselves: what does banning cousin marriage look like?
Practically, cousins would be added to the list of parties within the 'prohibited degrees of relationships' for marriage under the Marriage Act 1949. The list contains all the usual suspects: you cannot marry your own parent, child, grandparent, sibling, aunt, uncle, niece or nephew. If you try to marry someone on this list, you will be unable to get an official to perform the ceremony without lying to them, and if you lied, the marriage could be annulled.
There are two types of marriages liable to annulment. Firstly, voidable marriages: these can be annulled under certain circumstances, but will be considered valid if the parties wish it. Secondly, void marriages: those which can never be valid; legally treated as though they never existed.
If cousins were included in the list of prohibited degrees, the marriages would be void. Crucially there is a distinction between a relationship constituting a void marriage, and something that is just not a marriage (called a 'non-marriage'). A party to a void marriage can claim financial relief just the same as if they were divorcing; an important protection if the concern is that vulnerable young women are being coerced or pressured into cousin marriages.
However, if the parties cannot be legally married, they may choose to hold only a religious or social ceremony that would be considered a 'non-marriage' in the eyes of the law. The line between a void marriage and non-marriage in the case law is nebulous, but if the parties know they are not contracting a legal marriage, this will almost certainly be considered a non-marriage and the vulnerable 'wife' will have no more legal protection than a cohabitee.
Equally important to the conversation is to realise that entering a void or non- marriage is not necessarily a criminal offence. Adding cousins to the prohibited degrees of relationship only prevents cousins legally marrying; it does not prohibit romantic and sexual relationships between them.
Wait, you might think if I tried to marry my sister, surely the police would be knocking on my door?
Almost certainly they would. However, the crime is not the attempted marriage, it is the breach of the Sexual Offences Act 2003.
Issue of Sexual relationships
It is not necessarily a crime to try to marry someone within the prohibited degrees list, but that list overlaps with the list of people you cannot have sexual contact with under s27 of the Sexual Offences Act 2003. If you turn up at the town hall to marry your sister, the registrar is probably going to call the police because of the implied sexual relationship.
The big question for Parliament in banning cousin marriages is whether it would ban sexual relationships between cousins as well. Without an amendment to the Sexual Offences Act, there is nothing in the law that would prevent cousins getting religiously (but not legally) married, cohabiting as romantic partners, or having children. As explained above, this presents risks to the weaker partner – often the wife and mother. It also does not address the concerns about the genetic risks to potential children, nor does it address broader social concerns.
In addition, marriages which are validly contracted in another jurisdiction are generally recognised in England and Wales, even if that marriage would not meet the criteria for a valid marriage here. The case Cheni v Cheni [1965] P 85 even recognised a potentially polygamous marriage contacted between uncle and niece, on the basis that this was a valid marriage when it was performed in Egypt. Without prohibiting sexual contact between cousins, there would be nothing to stop cousins travelling abroad to marry and returning to England and Wales, with a recognised marriage.
Complications of banning Sexual Relationships
It is not simple to prohibit marriage and sexual relationships between cousins and call it a day. There are two significant complications.
The first is that while the proportion of marriages subsisting in this country between cousins is small, the number is not negligible. Parliament would have to grapple with a serious question of whether a prohibition on sexual relationships between cousins would apply to marriages validly contracted in good faith before the law changed. The state retrospectively prohibiting sexual relationships between validly married couples is an unpalatable thought. It would be straightforward to exempt couples married before the ban. A tricker issue is whether established couples who are cohabiting, and who may have been religiously married, would also be exempt.
The second complication is for those who are simply visiting the UK. Currently, the list of prohibited sexual relationships in each country is fairly universal. Human civilizations agree on very little, with the notable exception of taboos on parent-child and inter-sibling sexual relationships. Uncle/aunt/niece/nephew has historically had slightly more leeway, but not in the 21st Century. The chances of such consanguineous couples having a recognised relationship elsewhere, and then holidaying in Penzance, is vanishingly small.
In contrast, there is a wide range of cultural attitudes to cousin marriage: from prohibited, to taboo, to accepted, to encouraged. The Oxford Journal of Law and Religion estimates that 10% of the world's population practices cousin marriage. Estimates of first- and second- cousin marriage in Gulf States is around 40% of all married couples. This is a high number of people who might travel to this jurisdiction, for work, to invest, to live, to holiday. We must question whether we want to criminalise sexual contact between married couples who have travelled to see Buckingham Palace and the London Eye.
Moving Forward
The issues identified above are certainly surmountable. One of the key arguments against a ban on cousin marriage is that it would have little effect and be unenforceable. This is not, it itself, a reason not to: a ban still has a deterrent effect, it empowers those who do not want to participate in a practice, and it provides remedies to those who suffer disadvantages from it.
However, the upcoming Parliamentary debate needs far more nuance than the subject has been given to date. Discussions about banning marriage usually take for granted that sexual relationships would also be banned, without any consideration of the difficulties involved. The ban evidently has widespread support, but it is crucial that the discussion should be well-informed, and considerate of the British families who have founded their lives on cousin marriages in good faith.
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