Dozens of pro-immigrant demonstrators took to the street last Saturday outside the San Francisco home of Trump adviser Peter Thiel to protest his firm Palantir Technologies’ involvement with Immigration and Customs Enforcement. Protesters carried signs reading “Make America Mexico Again” and “No Ban No Wall No Surveillance State.”

“The reason we’re here,” said one speaker, “is to call upon the people who are complicit in what Trump is trying to do.”

As The Intercept reported on March 2, Palantir is building a $41 million data platform called Investigative Case Management that allows ICE agents, including those in the agency’s primary deportation force, the Enforcement and Removal Office, to query information across several large government databases simultaneously. Documents newly obtained by The Intercept state that Palantir software also permits ICE agents to access information from the Central Intelligence Agency.

Investigative Case Management makes available to its users a separate ICE system, also built by Palantir, called FALCON. This system was created for ICE’s office of Homeland Security Investigations, which is generally tasked with pursuing serious cross-border crimes like drug trafficking, child pornography, and terrorism, but has also been behind some of the most controversial deportation actions under Trump and Obama.

HSI agents can use FALCON, a customized version of Palantir’s Gotham software, to pull data from offices within the Department of Homeland Security, the FBI, and other sources that include information on foreign students, family relationships, employment information, immigration history, criminal records, and home and work addresses.

According to a set of FALCON funding documents from 2013 that were obtained by The Intercept, immigration officials can also use FALCON to access data held by agencies that possess highly classified intelligence, including the CIA and the National Counterterrorism Center.

“Palantir enables ICE/HSI to secure information sharing with other law enforcement agencies in real-time to include Transportation Security Administration (TSA), Custom & Border Protection (CBP), the United States Coast Guard (USCG), Federal Bureau of Investigations (FBI), National Counterterrorism Center (NCC), Central Intelligence Agency (CIA) and Defense Intelligence Agency (DIA),” a 2013 funding document states. “This will give ICE an open platform that will be interoperable and have the ability to cross use capabilities such as federated search, mapping and geospatial capability, unstructured search function, visual linking with these agencies and also have the capability to fully scale the solution to enable large entity exchange (e.g. petabytes of data) between our agencies.”

Jay Stanley, a privacy expert at the American Civil Liberties Union, worries that this type of data sharing, even if justifiable in certain circumstances, could potentially be repurposed to support ICE’s daily immigration policing.

“It seems like there could be very reasonable purposes for which the CIA would exchange information with ICE,” said Stanley. “These kind of information exchanges are often initially based on particular, hair-raising scenarios, but then the routine tool is created and ends up being used for all kinds of everyday petty enforcement.”