That number could be an underestimate, as well. MPI’s Pierce points out that the “especially problematic” aspect of the expanded policy is that it would require undocumented immigrants to “affirmatively” demonstrate, “to the satisfaction of an immigration officer” if they’ve been in the country more than two years — something that might be difficult to do for a population that avoids paper trails and lives largely in the shadows. That means a lot more people than currently estimated could be caught in this expanded dragnet, Pierce said.

Kathryn Shepherd, national advocacy counsel at the American Immigration Council, has worked with families seeking asylum in ICE detention centers who are in expedited removal proceedings. In a 2017 report, she wrote about the perils of the expedited removal process for legitimate asylum seekers, arguing that it restricts them from accessing counsel and often delays the process by which they can gain protection in the U.S.

With this new policy, she fears, apart from asylum seekers and undocumented immigrants with long ties to the country, even people with legal status may be affected. “The immigrant communities in this country are already terrorized by all these [Trump administration] policies,” she said. “This policy in particular would serve to really chill immigrant communities; there will be the very real possibility that immigrants will be swept up who should not be.”

Advocates are saying that the expanded policy would, in effect, create a “show me your papers” nation — forcing immigrants, and even many U.S. citizens, to carry proof that they are not deportable.

In June, Buzzfeed News first reported that the administration had been considering this move, although immigrants’ rights groups and attorneys have been bracing for something like this since President Donald Trump took office in 2017. After a series of executive orders, a DHS memo at the time had issued guidance mentioning the possibility of expanding expedited removal.