(NewsNation) — The Department of Homeland Security spent millions to buy cellphone location information from companies without getting warrants, a new report from the American Civil Liberties Union found.

Published Monday, the ACLU’s report shows that the Department of Homeland Security, including Customs and Border Protection and Immigrations and Customs Enforcement, bought access to cellphone location information from citizens’ and migrants’ smartphone apps. This information was aggregated and sold by two companies, Venntel and Babel Street.

“These records provide critical insight into the government’s attempts to wash its hands of any accountability in purchasing people’s sensitive location data when it would otherwise need a warrant,” Shreya Tewari, the Brennan Fellow for ACLU’s Speech, Privacy, and Technology Project, said in a statement.

The Wall Street Journal was the first to report ICE’s and CBP’s warrantless purchase of access to people’s information. Then, the ACLU submitted a Freedom of Information Act request to the agencies as well as DHS. In December 2020, the ACLU sued to force the agencies to respond to their request. Litigation in that suit is ongoing, with the ACLU calling the purchase of information for the agencies a move to sidestep the Fourth Amendment right against “unreasonable government searches and seizures.”

“We’re increasingly alarmed at the ways that police departments, including the Department of Homeland Security, are using taxpayer money as an end run around the Constitution,” said Albert Fox Cahn, executive director of the Surveillance Technology Oversight Project. “Police have really broad powers to go and use subpoenas and warrants to get our data. But what we’ve seen in recent years is that a lot of departments, instead of actually ordering companies to hand over information, are going even further, and simply buying our data, including our location data from vendors.”

More than 6,100 pages of location records reviewed by the ACLU contain about 336,000 location points obtained from people’s phones. Records from one three-day span in 2018 contained around 113,654 location points, or more than 26 points per minute. Most of that data appears to come to come from one area in the Southwestern United States, the ACLU said, making it just a small subset of the total volume of people’s information available to the agency.

According to Venntel marketing materials sent to DHS, the company explained how it collects more than 15 billion location points from over 250 million cell phones and other mobile devices every day. Using the data, law enforcement can identify devices observed at places of interest, and “identify repeat visitors, frequented locations, pinpoint known associates and discover patterns of life.”

Mark Morgan, a former chief operating officer and commissioner of U.S. Customs and Border Protection, said the data is used to carry out basic investigative actions to further the agency’s mission.

“Most federal law enforcement agencies use similar publicly available data, along with a variety of intelligence capabilities, in support of a variety of enforcement operations,” Morgan said.

One area of concern the ACLU had was for people living near the U.S. border. The organization cited a 2018 DHS internal document that proposed using the data to identify illegal immigration patterns.

Cahn argues that federal agencies spending money to track down people along the border zone isn’t effective.

“Instead, we need to be looking at the factors that are driving so many people to flee for safety on our shores, not trying to turn the southern border into some sort of dystopian fortress,” he said.

The Wall Street Journal wrote that ICE, under the Trump administration, used the data collected from people’s phones to help identify immigrants who were later arrested.

Politico notes that the location tracking continued into the Biden administration after Customs and Border Protection renewed a $20,000 contract to get the data, which initially ended in September 2021.

But deportations and arrests for illegal immigration activity have dropped significantly under President Joe Biden. The Washington Post reported earlier this year that the number of deportations fell sharply in 2021, to the lowest levels in the agency’s history. According to the Washington Free Beacon, 2,896 migrants apprehended on the southwest border were transferred into U.S. Marshals Service custody in the 2021 fiscal year, compared to 13,213 in 2020.

NewsNation has reached out to the Department of Homeland Security, Venntel and Babel Street for comment. Documents the ACLU obtained show the agencies and companies have said the information they collect has no “personally identifying information” because it is associated with a phone number, not a name. Documents also asserted that cell phone users “voluntarily” share location information, collected with the consent of the app user. But the ACLU noted that many cellphone users don’t realize how many apps collect GPS information, and don’t know that data is sold to the government in bulk. Additionally, the ACLU said, the entire purpose of the data is to be able to identify and track people.