Immigration policy that helped Haitians, Cubans on trial

• The administration says the program has helped reduce the number of illegal crossings at the southern border.

Driving the news: A group of 21 Republican-leaning states, led by Texas, argue the White House is not enforcing an immigration law that says humanitarian parole should only be used on a "case-by-case basis for significant public benefit or urgent humanitarian reasons."

By the numbers: More than 72,000 Haitian migrants, 63,000 Venezuelans, 41,000 Cubans and 34,000 Nicaraguans had been authorized to enter the U.S. through the program as of last month, per the Associated Press.

What's next: The trial began Thursday and is expected to end Friday, with the judge in the case issuing an order at a later date, the AP reports.