New iris-scanning technology used along the U.S.-Mexico border could exacerbate racial profiling.

Before President Trump ever builds his “big, beautiful wall,” there could be a fortified virtual wall at the U.S.-Mexico border bristling with biometric technology.

In the coming months, 31 counties along and near the border — including more than a dozen in Texas — will deploy a system that can “capture, catalogue, and compare individuals’ iris data, for use both in jails and out on patrol” with mobile, smartphone-based scanners, according to The Intercept.

The private company that built the system, Biometric Intelligence and Identification Technologies (BI2), has offered sheriffs’ departments along the border a free, three-year introductory trial of its IRIS biometric identification program. According to the company, the technology gives fewer false matches than fingerprinting.

Cameron County Sheriff Omar Lucio will be one of the first to use the scanner in his department’s day-to-day policing.

Lucio said the technology will help his deputies identify undocumented immigrants. “It’s not unusual for people caught illegally from Mexico to give fake names and date of births,” he told The Intercept. “But it doesn’t matter what you use if we have your features — your iris, your fingerprints. You can use a hundred different names. We still can say, ‘This is the guy.’”

But civil liberty experts say the technology could exacerbate racial profiling, giving law enforcement officers the ability to determine criminal history or citizenship with an instant scan. “In this country, we’ve long resisted being a ‘show me your papers’ society, but this moves us to that because you increasingly can’t avoid your identity being scooped up in public,” Nathan Wessler, staff attorney with the Speech, Privacy, and Technology Project of the American Civil Liberties Union, told The Intercept.

“Racial profiling is a serious concern, especially Latinos or people of color are at greater risk for iris checks simply for the color of their skin,” he told the publication.

Another fear is that all of the biometric data will automatically be stored by BI2 Technologies in its private database on a server in San Antonio. As The Intercept reports, “to make an identification, BI2’s iris recognition program compares an individual’s iris against the over 987,000 iris scans held in its private database, which collects images from over 180 law enforcement jurisdictions nationwide.” The database grows with each new scan.

The Department of Homeland Security already collects biometric information at ports of entry, including airports. But U.S. citizens’ information is discarded after making the verification, while non-citizens have their information stored for 75 years. With the implementation of this new border program, a private company will be able to amass an untold amount of sensitive biometric information — not just from undocumented immigrants but also from U.S. citizens.

Editor’s note: This story has been updated to reflect proper attribution to The Intercept’s reporting.