The US supreme court on Tuesday left in place for the time being a pandemic-era order allowing US officials to rapidly expel migrants caught at the US-Mexico border in order to consider whether 19 states could challenge the policy’s end. The court on a 5-4 vote granted a request by a group of Republican state attorneys general to put on hold a judge’s decision invalidating the emergency order known as Title 42 while it considered whether they could intervene to challenge the ruling. The states had argued lifting the policy could lead to an increase in already-record border crossings. John Roberts, the chief justice of the US supreme court , a member of the court’s 6-3 conservative majority, on 19 December issued a temporary administrative stay maintaining Title 42 while the court considered whether to keep the policy in place for longer. The policy had been set to expire on 21 December prior to his order. Conservative Justice Neil Gorsuch joined with the court’s three liberal members – Justices Sonia Sotomayor, Elena Kagan and Ketanji Brown Jackson – in dissenting from Monday’s order leaving Title 42 in effect. Title 42 order was first implemented in March 2020 under Republican former president Donald Trump at the beginning of the Covid-19 pandemic. Joe Biden, a Democrat, kept the restrictions in place for more than a year after taking office in 2021 despite promising to shift away from hardline immigration policies adopted by Trump. US Border Patrol agents apprehended a record 2.2 million migrants at the south-west border in the 2022 fiscal year, which ended 30 September. Close to half of those arrested were rapidly expelled under the Title 42 policy. The Biden administration sought to lift Title 42 after US health authorities said in April that the order was no longer needed to prevent the spread of Covid-19, but were blocked by federal judge in Louisiana – a Trump appointee – in response to a Republican-led legal challenge. Separately, a group of asylum-seeking migrants represented by the American Civil Liberties Union (ACLU) had sued the government over the policy, arguing the expulsions to Mexico exposed them to serious harms, like kidnapping or assaults. In that case, US district judge Emmet Sullivan in Washington, DC, sided with the migrants on 15 November and ruled Title 42, which has been used to expel hundreds of thousands of people since its inception, was unlawful. Sullivan, an appointee of Bill Clinton, a Democratic former president, said the government failed to show the risk of migrants spreading Covid-19 was “a real problem”. He said the government also failed to weigh the harm asylum seekers would face from the Title 42 order. The Biden administration sought time to prepare for the end of the policy, at which point migrants would be able to once again, as they had pre-pandemic, be allowed to request asylum at the border. Sullivan gave it until 21 December. Unhappy with the lower court’s decision, a group of Republican state attorneys general sought to intervene to keep defending the policy in court. When a federal appeals court on 16 December declined to allow them to intervene and put Sullivan’s order on hold, they took the matter to the US supreme court.