Throughout his campaign and now his presidency, historians have drawn parallels between President Trump’s treatment of the news media and the Nixon White House’s efforts to influence coverage in its favor during Watergate.

In yet another eerie echo of that grim chapter in history, reports surfaced in March that U.S. Customs and Border Protection (CBP) had compiled a watchlist and dossiers to monitor and target journalists covering migrants arriving at the U.S.-Mexico border, as well as activists and lawyers who frequently interact with them.

Now, CBP has confirmed in a letter that it collaborated with the Mexican government and other law enforcement agencies to collect information about these individuals because the Mexican Federal Police identified them as “possibly assisting migrants in crossing the border illegally and/or as having some level of participation in the violent incursion events.”

There is much we don’t know about the CBP dossiers, but even still, their creation may violate the Privacy Act of 1974 — passed in the wake of Watergate and revelations of “White House enemies lists” and secret government surveillance programs — which generally prohibits the government from collecting detailed records on a person based on an individual’s exercise of First Amendment rights.

Revelations of domestic surveillance of journalists and others exercising First Amendment rights were in the minds of lawmakers considering the Privacy Act prior to its passage. One example was the FBI’s COINTELPRO, a secret program in which the FBI targeted various political organizations that it deemed “subversive.” Using information gathered through illegal surveillance of individuals, agents were directed to harass, intimidate, and discredit the leaders of the targeted groups.

The program ended in 1971 after activists broke into an FBI office in Media, Pennsylvania, and leaked COINTELPRO dossiers to The Washington Post. In a supreme bit of irony, noise from the “fight of the century” between Joe Frazier and Muhammad Ali — himself a COINTELPRO target — provided cover for the break-in.

Around the same time, investigative reporters revealed that the CIA had been monitoring and maintaining files on groups like the Southern Christian Leadership Conference, a prominent civil rights organization. The program was code-named “Operation CHAOS,” and it also targeted the press, including Ramparts magazine, the predecessor to publications like Mother Jones and Rolling Stone.

A 1975 presidential inquiry known as the Rockefeller Commission found the CIA’s domestic spying was in violation of its authorizing statute. The commission’s report exposed a CIA index of more than 7 million names, about 115,000 of whom were believed to be U.S. citizens. The CIA also created at least 57,000 dossiers on American citizens, most of whom were not connected to foreign intelligence activities.

Finally, there was Project Minaret, a National Security Agency (NSA) program that maintained a watchlist and tapped the overseas communications of prominent journalists and Vietnam War critics. A recently declassified NSA history of the program — which called it “disreputable if not outright illegal” — revealed that Minaret tapped the calls and cables of Sen. Frank Church (D-Idaho), who ultimately led the eponymous Senate committee investigating all of these programs.

Public disclosures of these watchlists and dossiers, in addition to passage of the Privacy Act, led to congressional investigations like the Church Committee and eventually a series of reforms such as passage of the Foreign Intelligence Surveillance Act, and the creation of the Foreign Intelligence Surveillance Court, which oversees searches and surveillance in certain types of intelligence cases. The Justice Department also adopted guidelines that limit investigations based on First Amendment-protected political activities (though with many unfortunate exceptions).

When it comes to CBP, however, the potential for abuse through harassment and disruption of legitimate First Amendment activities could be much higher than that by the FBI, CIA, and NSA, all of which operate under some external and internal constraint.

CBP is the largest law enforcement agency in the country — and one of the largest in the world. It operates with enormous resources, discretion, and authority. Yet, despite its size and potential reach into our private lives, the public knows little about how CBP operates.

The lessons from history are clear: public controversies, such as the tumult over the Vietnam War — and perhaps the contemporary debate over immigration — can lead to overreach and secret programs that target and harass journalists and others. Collection of personal information on the exercise of legitimate First Amendment rights gives the government power to disrupt those activities, and that power can corrupt. CBP’s vast authority must be balanced by greater accountability and transparency. We need to know precisely what CBP is doing with watchlists and dossiers and whether their creation was lawful in the first place.

IMAGE: The end of a section of the border barrier stands on the U.S. side of the U.S.-Mexico border, with Tijuana in the background, on April 3, 2019 in Otay Mesa, California. (Photo by Mario Tama/Getty Images)