A United States federal judge has barred the Trump administration from changing asylum laws. The judge stopped a presidential order that would have blocked immigrants from seeking asylum if they entered the United States illegally. President Donald Trump signed the order on November 9. It denied asylum to anyone who crossed the southern border without going through official ports of entry. He acted in answer to large groups of Central Americans currently walking to the U.S. border with Mexico. They have said they plan to enter the U.S. Many are fleeing violence in their homelands. Trump described the so-called “caravan” of Central Americans as a national security threat. U.S. troops are deployed to the border to help stop what Trump has also called an “invasion.” But on Monday, the judge in the case said that the president is not permitted to “rewrite the immigration laws to impose a condition that Congress has expressly forbidden.”