WHY NOW? The US Supreme Court on Thursday (May 15) will hear arguments over the legality of an executive order issued by President Donald Trump that seeks to end birthright citizenship. It is aimed at children born in the United States to undocumented immigrants and temporary visa holders. The outcome of the case could determine the future course of American citizenship law. WHAT IS BIRTHRIGHT CITIZENSHIP? According to the 14th Amendment to the Constitution, “All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside.” Additionally, the Citizenship Clause, ratified in 1868 after the American Civil War, aimed to ensure that formerly enslaved people would be citizens. Until 1924, sovereign Native American tribes were exempt from the law. The provision has been widely interpreted to make citizens of anyone born on American soil, except for: The children of diplomats who have allegiance to another government. Enemies present in the US during hostile occupation. The concept itself is centuries old and is based on the English common law principle of ‘jus soli’, or ‘right of soil’, granting automatic citizenship to anyone born within a country’s boundaries regardless of the nationality of their parents. WHY DOES TRUMP WANT TO END BIRTHRIGHT CITIZENSHIP? On his first day of office, Trump signed an executive order denying citizenship to children of parents who were not themselves US citizens or lawful permanent residents. According to the order, this targeted people who were illegally or temporarily present in the country because they are not “subject to the jurisdiction” of the United States. In his first post-election interview in December, Trump said, “We have to end it. We’re the only country that has it.” IS THE US REALLY THE ONLY COUNTRY TO PRACTISE BIRTHRIGHT CITIZENSHIP? No. At least 37 other countries grant citizenship to anyone born on their soil, mostly in South America and the Caribbean. India does not practice unconditional birthright citizenship, nor do several European countries. WHAT WILL THURSDAY’S RULING CONCLUDE? Three federal judges have issued nationwide injunctions staying the order, which Trump alleges is a breach of their authority. The US Supreme Court is thus hearing an emergency appeal by the Trump administration to enforce its executive order even as lawsuits over the order are heard. However, the constitutionality of the order is not up for legal consideration before the court just yet.