Opponents are suing to end a federal program that could potentially give nearly half a million migrants without legal status who are married to US citizens a path to citizenship. Sixteen Republican-led states filed suit on Friday to halt the program launched by Joe Biden in June, saying in court filings that the Biden administration bypassed Congress to create a pathway to citizenship for “blatant political purposes”. Under the policy, which started taking applications on Monday, many spouses without legal status can apply for something called “parole in place”, offering permission to stay in the US, apply for a green card and eventually get on a path to citizenship. But the program has been particularly contentious in an election year in which immigration is a leading issue, with many Republicans attacking the policy and labeling it amnesty for people who broke the law. The Texas attorney general, Ken Paxton, said in a statement on Friday that the plan “violates the Constitution and actively worsens the illegal immigration disaster that is hurting Texas and our country”. The suit filed against the Department of Homeland Security, the DHS secretary, Alejandro Mayorkas, and other Biden administration officials accuses the agency of attempting to parole spouses “en masse”, which the states contend is an abuse of power. The Department of Homeland Security and the White House did not immediately respond to a request for comment from the Associated Press. The bipartisan immigration and criminal justice organization FWD.us noted the timing of the lawsuit, which was filed on the night Kamala Harris accepted the Democratic nomination for president, and said the program was in compliance with the law. “The only motivation behind this lawsuit is the cruelty of tearing families apart and the crass politics of hoping a judge might do the bidding of the anti-immigrant movement,” the organization said in a statement. To be eligible for the program, immigrants must have lived continuously in the US for at least 10 years, not pose a security threat or have a disqualifying criminal history, and have been married to a citizen by 17 June. They must pay a $580 fee to apply and fill out a lengthy application, including an explanation of why they deserve humanitarian parole and a long list of supporting documents proving how long they have been in the country. They apply to the Department of Homeland Security, and if approved, have three years to seek permanent residency.