The act is a wartime authority that allows the president to detain and deport non-U.S. citizens from enemy countries.

The president could deploy the little-known law as part of his sweeping crackdown on immigration as early as Friday, reports say. Here’s what to know. President Donald Trump said in his inauguration address that he planned to utilize the Alien Enemies Act of 1798 as part of his sweeping crackdown on immigration.

President Donald Trump is expected to invoke the Alien Enemies Act, a wartime law granting the president authority to detain or deport nationals of an enemy country, two U.S. officials familiar with the matter told ABC News.