This April 16, 2014 photo shows Laura Poitras, left, and Johanna Hamilton in New York to promote their documentary film "1971," premiering Friday at the Tribeca Film Festival. (Photo by Charles Sykes/Invision/AP)

NEW YORK (AP) -- A trove of government documents reveals widespread domestic surveillance of Americans. Leaked revelations hit the front pages of newspapers. A powerful governmental agency is brought under scrutiny.

Sound familiar?

It's the story of the documentary "1971," premiering Friday at the Tribeca Film Festival, a film about a little-known but hugely important break-in on March 8, 1971. A group of eight calling themselves the Citizens' Commission to Investigate the FBI broke into a laxly guarded satellite FBI office in Media, Pennsylvania, outside Philadelphia. They found files that proved the extensive spying that J. Edgar Hoover's FBI was conducting on dissident groups, civil rights leaders and anti-Vietnam War activists. It was the initial revelation of Hoover's covert Cointelpro (counterintelligence) program.

If "1971" was a blockbuster, it would be called a prequel. In many ways, the story is an early echo of the National Security Agency and the Edward Snowden affair, only in a less technologically sophisticated time. (The manhunt for the burglars focused partly on tracing the photocopy machine they used.)

"My concern all along prior to Snowden was that people would view it as this quaint bit of history," says director Johanna Hamilton, who began working on the film four years ago. "Now, that's much less easy to do. I've always sort of laughed that they're the analog version."

The connection between "1971" and the NSA revelations isn't just historical metaphor. Laura Poitras, the journalist and documentarian, is a producer on the film. Snowden, an NSA contractor, initially contacted Poitras about leaking thousands of documents that revealed the NSA's collecting of Americans' phone and email records. On Monday, she shared in the Pulitzer Prize for public service given to The Washington Post and The Guardian for the NSA revelations.

In an exclusive interview, Poitras and Hamilton reflected on the connections between the two eras, both times of privacy intrusions revealed by government document theft. Though "1971" never explicitly refers to the NSA or Snowden, its thick contemporary relevance is hard to miss.

"You would have to be living in a cave not to pick up on it," says Poitras.

The burglars of Media, who anonymously mailed copies of the stolen documents to three newspapers, were never caught. "1971" was made in tandem with a book by Betty Medsger, "The Burglary: The Discovery of J. Edgar Hoover's Secret FBI," published earlier this year. (Medsger was the Washington Post reporter who broke the story in 1971.)

At the publication of the book, five of the eight revealed their identities and they're featured on camera in the film. (They likely can no longer be tried for the break-in.) Led by then-Haverford College physics professor Bill Davidon (who died last year), they're a collection of regular citizens, including a cab driver and a social worker. Two of them, Bonnie and John Raines, had three kids at the time. With family photos and old video, "1971" presents the burglars not as political firebrands, but as typical Americans.

"They're ordinary Americans who decided to take a stand," says Hamilton, a producer of the Oscar-nominated documentary "Pray the Devil Back to Hell."

To Poitras, the Citizens' Commission is similar to Snowden in that they took great risk for a cause they believed in.

"It's obviously an act of conscience," she says. "They didn't want to leave such a world to their kids. The sacrifice is extraordinary and obviously parallels with the sacrifice that Snowden has also made. A young man who really puts his life on the line to reveal to the public what the government is doing is exactly the choice that they made."

But to Poitras, much has changed, as well. The publication of the NSA material was far more labored. (Post executive editor Ben Bradlee, who would publish the Pentagon Papers just months later, published within a day of receiving the stolen FBI documents.) She has been chilled by the legal pursuit of whistle-blowers and journalists, citing New York Times journalist James Risen. He risks jail for refusing to testify in a case revolving around the leaking of CIA information.

Snowden has been charged with espionage and other offenses in the U.S. and could get 30 years in prison if convicted. He has received asylum in Russia. President Barack Obama has assigned two panels to conduct reviews of the NSA surveillance programs.

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