A judge has temporarily blocked new immigration policy allowing undocumented spouses of U.S. citizens to apply for green cards without having to leave the country. The program only started accepting applications last week – but a group of Republican-led states quickly sued – claiming the policy is unconstitutional. The Biden administration has vowed to fight back. This is the latest friction point on what is shaping up to be one of the most important issues in this year’s presidential election. Toni Waterman reports.