Marrying your first cousin is legal in the UK- How this week in politics could change that

In the UK, marriage laws prohibit unions between siblings, parents, and children, however, first-cousin marriages remain legal. This week, Conservative former minister Richard Holden is set to challenge this, presenting a Bill to the House of Commons that could outlaw such relationships.

Holden argues that first-cousin marriages are associated with significant societal and health concerns and wishes to challenge this by presenting his Bill to the House tomorrow. “Such marriages have been linked to a higher rate of birth defects and can also reinforce negative structures and control women,” he says.

His proposal has sparked debates about personal freedoms, cultural practices and public health. This is despite research consistently showing that first-cousin marriages do carry a heightened risk of genetic disorders in offspring.

A long-term health study called Born in Bradford was conducted on thousands of people born in the city between 2007 and 2011. The study found that the risk of birth defects in children of first cousins is 6%, compared to 3% in the general population. These figures are even more pronounced in communities where cousin marriages are common across generations, as genetic conditions can accumulate over time.

While the overall risk remains relatively low, these statistics raise ethical questions about the practice. Public health officials have noted the strain these cases can place on healthcare systems, particularly in areas with high concentrations of such marriages.

Cousin marriages are legal in many countries, including the United States, Canada and across Europe. In some communities, they are deeply rooted in tradition, offering social and economic benefits such as keeping wealth within families.

Holden’s proposal highlights tensions surrounding respecting cultural practices and safeguarding individual freedoms. “Marriage and relationships should be about individual choice in modern Britain. It shouldn’t be about anything else,” he says.

Robert Jenrick also gave his support to this Bill, saying: “Frankly, it should have been banned a long time ago.”

Critics argue that banning cousin marriages could unfairly target specific cultural groups and infringe on personal liberties. Others counter that the practice perpetuates patriarchal structures, limiting women’s autonomy in marriage decisions. Many X (formerly Twitter) users say that the decision should have been made years ago or assumed that it was already law.

Despite the controversy, cousin marriages are not unheard of among public figures. Queen Victoria and Prince Albert, one of history’s most famous couples, were first cousins. Their union, while celebrated for its romance, had genetic consequences: their descendants exhibited a higher prevalence of haemophilia, a rare bleeding disorder.

In more recent times, Rudy Giuliani, former mayor of New York City, was married to his second cousin, Regina Peruggi, for 14 years. While their relationship did not result in children, it demonstrates how cousin marriages persist even in modern, high-profile contexts.

Kevin Bacon is also married to his ninth cousin, claiming that they had no idea they were related - and to be fair to him, most people probably don’t know their ninth cousin either. To clarify, a ninth cousin is a distant relative who shares a great-great-great-great-great-great-great-grandparent.

The former US president Roosevelt was married to his fifth cousin once removed, Anna Eleanor Roosevelt. This means they would go back six generations.

After presenting his Bill to the House on Tuesday, Holden will hope that it progresses through the House of Commons and get approval from the House of Lords, as well as Royal Assent, after which it would become law.