President Donald Trump has promised to remove millions of people from the United States in the largest deportation program in American history. But his immigration agenda is facing various tests in the U.S. courts.

For example, a federal appeals court ruled last week that the Trump administration cannot use an 18th-century wartime law to speed deportations of alleged Venezuelan gang members, setting up a likely return showdown at the Supreme Court.

Recommended Videos

Some of the president's policies affect hundreds of thousands, if not millions, of people. Here are some Trump administration efforts that have come under court scrutiny:

Alien Enemies Act

The Trump administration has used the Alien Enemies Act of 1798 to remove people it accused of being in the Tren de Aragua gang,

See Full Page