“We saw a pretty significant drop in the latest data we got from U.S. Immigration Customs Enforcement down to under 18,000,” Austin Kocher, a TRAC researcher, told Border Report on Monday.

Kocher attributes the drop in detentions to these reasons:

• Fewer migrants are being put into detention at the U.S./Mexico border.

• A drop in interior enforcement arrests of migrants.

• More migrants are being paroled into the United States to await asylum proceedings under the Department of Homeland Security’s Alternatives to Detention (ATD) program.

“It’s enormous. All of the action on the immigrant detention side is in Alternatives to Detention. There’s been a huge investment from Immigration and Customs Enforcement,” Kocher said.

The ATD program utilizes technology, like smartphones and telephonic reporting by migrants to check in with DHS officials under what the agency calls “case management.”

But Kocher said there is growing concern within migrant advocates that DHS officials are tapping into much more information on the migrants via these devices.

“The big change is they’re using smartphones with facial recognition technology, and while that is contributing to lower numbers of detentions, there are concerns that the use of that intensive kinds of tracking — not just using geo-locations but using facial recognition technology — having access to migrants’ smartphones may present other concerns to privacy and confidentiality that we just don’t understand yet,” Kocher said.