The number of federal judges blocking President Trump’s executive order to end birthright citizenship in the US has risen to three, as judges in Maryland, Washington, and New Hampshire all make moves to prevent the GOP’s election pledge.

The United States is one of around thirty countries worldwide where the principle of jus soli or “right of the soil” citizenship is applied. This has been the case since the 14th Amendment was ratified in 1868 during the post–Civil War reconstruction era of the United States. The Constitution states that “All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States”. Conservatives in the US have long argued that this amendment is a magnet for illegal migration and “birth tourism”, describing people deliberately travelling to the US in order to have their child on US soil.

Representatives from the Trump administration also argue that the amendment excludes those born in the US to undocumented illegal migrants and are adamant that the president’s order is an integral part of his plan to address the country’s “broken” immigration system.

On the 5th of February, the following statement was made by Maryland District Judge Deborah Boardman: “Today, virtually every baby born on US soil is a US citizen upon birth, [...] That is the law and tradition of our country.” Her comments came two weeks after the US District Court Judge in Seattle, John Coughenour, called the 47th president’s executive order “blatantly unconstitutional” and imposed a two-week hold on all proceedings. The states of Washington, Illinois, Oregon, and Arizona also asked for the order to be paused while their federal judges consider states legal challenges to the “mind-boggling” order.

The pause on the president’s executive order will carry on until the proper legal process plays out—a task which could take the legal system several months, or even years. Constitutionally speaking, in order to carry out a direct change to the US Constitution, the president must enact a “constitutional amendment” rather than an executive or legislative order. Executive orders can in some cases be carried out without the approval of Congress, and new legislation only needs a majority in Congress—something which Trump has—to pass into law. Crucially, however, a constitutional amendment (which this is) can only be ratified by a congressional supermajority in both the Senate and the House of Representatives. A supermajority would require two-thirds of both houses voting in favour of altering the 14th Amendment. Delegates from both the Republican and Democratic party must vote in favour of Trump. It remains to be seen in what possible way President Trump would seek to bypass such a strict constitutional requirement.