Judy Woodruff:

Nearly 100,000 undocumented immigrants were detained at the U.S. southern border last month. But it is what happens after they are held in U.S. custody that has come under scrutiny in recent weeks.

The federal Department of Homeland Security and members of Congress have released accounts of the overcrowding inside detention facilities. Supporters of the Trump administration's policies say they are a continuation simply of the Obama years.

Jeh Johnson served as the secretary of homeland security during the Obama administration. And he joins me now.

Jeh Johnson, welcome back to the "NewsHour."