The Trump administration will begin turning back asylum-seekers at border crossings, forcing migrants fleeing violence to remain in Mexico while they await their day in U.S. immigration court.
Before this change in policy, people who were looking to the United States for refuge could pass a "credible fear" test, and remain in the country.
With this new policy, migrant families seeking asylum must stay on the Mexico side of the border, often in squalid camps.
The United States currently has a backlog of over 800,000 immigration cases, a wait that has been exacerbated by the partial government shutdown.