The United States is pouring money into surveillance technology along the southern border.

According to the EFF, the agency plans to triple the number of building towers from the current 135 to 442 and upgrade the existing towers with new technologies over the next several years.

There are three different types of towers: integrated fixed towers, remote video surveillance systems, and stand-alone surveillance towers. All focus on detecting people from a distance, and developers of the first two types say they can detect people from up to 7.5 miles away with sophisticated cameras, radar sensors and lasers on the towers. The autonomous surveillance towers are the newest of the bunch, and while they have a short range — they can detect a person from 1.7 miles away — they’re equipped with motion-detecting radar and detection AI that can analyze images without human review.

According to CBP’s 2023 budget, the agency plans to consolidate all towers into one interoperable program and eventually erect a total of 723 towers between the north and south borders.

But for all the technology, Mays says, the goal of the program isn’t entirely clear: “I’ve never heard a well-articulated explanation of what the goal is.” Is the goal to prevent people from crossing the border? Is it to register people crossing the border? Is it to intercept people crossing the border? Like… what?”

So why is the program expanding so much? We’re not entirely sure, and the agency declined to comment on the record. According to Maas, the reasons are based on the crisis thinking of agencies responding to migration in border areas. “That’s all you hear. border crisis border crisis,” he says, but often the real crises occur at points of entry or along common migration routes. You don’t need a surveillance tower to know there’s a group of asylum seekers camped under the El Paso Bridge.

Maas said he found evidence of the United States using surveillance towers on the border as early as the 1930s, but the dangers of advanced, more comprehensive and more precise technologies, especially when targeting border communities, are real.

All of the surveillance is disrupting the daily lives of those communities, and a recent report from the ACLU of Texas found that residents’ mental health, whether perceived or real, is greatly affected by surveillance. David Donati, an attorney for the group, said the survey showed that “most people avoided going to important places like grocery stores, hospitals, polling places and community centers because they were afraid of encountering border guards.”

Donati also noted that immigrants often enter the U.S. legally and without trying to evade authorities, so tracking technology is not needed in most cases. As legal options shrink, potential immigrants turn to more dangerous ones, but Donati says more surveillance won’t solve the underlying problem.