The United States has the only bans on cousin marriage in the Western world. As of February 2010, 30 U.S. states prohibit most or all marriage between first cousins, and a bill is pending in Maryland which would prohibit most first cousins from marrying there. Six states prohibit first-cousin-once-removed marriages. Some states prohibiting cousin marriage recognize cousin marriages performed in other states, but despite occasional claims that this holds true in general, laws also exist that explicitly void all foreign cousin marriages or marriages conducted by state residents out of state.
Data on cousin marriage in the United States is sparse. It was estimated in 1960 that 0.2% of all marriages between Roman Catholics were between first or second cousins, but no more recent nationwide studies have been performed. It is unknown what proportion of that number were first cousins, which is the group facing marriage bans. To contextualize the group’s size, the total proportion of interracial marriages in 1960, the last census year before the end of anti-miscegenation statutes, was 0.4%, and the proportion of black-white marriages was 0.13%. While recent studies have cast serious doubt on whether cousin marriage is as dangerous as is popularly assumed, professors Diane B. Paul and Hamish G. Spencer speculate that legal bans persist in part due to “the ease with which a handful of highly motivated activists—or even one individual—can be effective in the decentralized American system, especially when feelings do not run high on the other side of an issue.”
Among supporters of repealing the laws, the Cousin Couples organization describes itself as “the world’s primary resource for romantic relationships among cousins including cousin marriage.” This group likens laws against cousin marriage to the anti-miscegenation laws of decades past. Their website includes legal and religious information and a message board.
A bill to repeal the ban on first-cousin marriage in Minnesota was introduced by Phyllis Kahn in 2003, but it died in committee. Republican Minority Leader Marty Seifert criticized the bill in response, saying it would “turn us into a cold Arkansas.” According to the University of Minnesota’s The Wake, Kahn was aware the bill had little chance of passing but introduced it anyway to draw attention to the issue. She reportedly got the idea after learning that cousin marriage is an acceptable form of marriage among some cultural groups that have a strong presence in Minnesota, namely the Hmong and Somali.
