Hoback’s film includes a tense clip of a conversation between the filmmaker and Facebook CEO Mark Zuckerberg. Above, Zuckerberg delivers a keynote address during the Facebook f8 conference on September 22, 2011 in San Francisco, California. (Justin Sullivan/GETTY IMAGES)

Filmmaker Cullen Hoback was about a year into working on a film on how technology is changing society when he realized that his footage was actually leading him in a different direction — the erosion of online privacy.

“I started out by asking the question of how technology is changing us,” Hoback told The Washington Post in an interview. “I interviewed all these people and was really dissatisfied with my answer. I realized that I had to look at what was behind the technology.”

The result was “Terms and Conditions May Apply,” a new documentary on the tech industry, the current state of online privacy and the role the government plays in data collection. The movie opened in select cities around the country last week, could hardly have come at a more opportune time in light of the disclosures about National Security Agency surveillance programs that collect data on foreigners and average Americans from prominent technology firms.

“It is kind of like a horror film,” Hoback said in describing his work. “I was able to look back and distill how we got here and really break down the relationship between the corporations and the government.”

Hoback draws a line between the shifts in Web users’ online privacy and laws that encourage data retention for national security concerns.

“There were over 10 bills on the floor [of the House and Senate] that were supposed to embed some sort of privacy rights. Then 9/11 happened, and that all got washed away,” he said.

But, as is clear from Hoback’s film, he doesn’t believe that the blame rests solely with the government.

“Just because these laws exist, it doesn’t mean that companies [that have provided the data to the government] couldn’t have sat up and tried to change them,” he said. “It seems in­cred­ibly convenient for them, getting an incredible amount of our data. They could be potentially building these systems with privacy at the forefront. It’s really more like the corporations had a lot to gain and the government had a lot to gain.”

He said major technology firms — Google, Facebook and LinkedIn are all featured prominently in the film — have not only taken steps to boost their data collection and retention but have also made it difficult for consumers to parse their lengthy terms and conditions statements for online privacy. Those agreements, which many users approve without reading, are so complicated that they may as well be invisible, he said.

“They’re designed not to be looked at, designed to be scoffed at,” Hoback said. “It’s a joke.”

Hoback said he wanted to make the film to make more lawmakers and Web users aware of online privacy issues, and to show that most people want explicit control over their own data. As part of that effort, Hobart has worked with Internet activist group Demand Progress to set up a Web site — trackoff.us — that directs people to contact their congressional representatives with privacy concerns.

To illustrate his point in the film, Hoback intercepted Mark Zuckerberg as he walked to work — after failing to reach him through official channels — to ask the Facebook chief executive about online privacy. When Zuckerberg asked Hoback to stop filming the conversation with his main camera, the filmmaker complied but continued to record with a camera concealed in his glasses.

The reason for filming that exchange, Hoback said, was to prove that privacy matters to everyone.

“We don’t want to be recorded just as much as you don’t want to be recorded,” he said. “With that [scene] I said, Mark, I’m opting you in even though you didn’t necessarily want that.”

Based on the reaction he’s seen to his film, he said, he believes there’s plenty of popular support for stronger privacy laws and regulations.

“People are scared and angry, and they want to do something,” he said.

But those efforts won’t be simple or easy. The technology industry moves fast, making it harder to form regulations quickly enough for new gadgets such as wearable technologies, he said.

“As these technologies get closer and closer to our bodies, the privacy protections will be more difficult,” to put in place Hoback said. “But the power is in the information.”

Hoback said that a recent vote in Congress defeating a provision that would have curbed NSA data collection shows that the fight for privacy is just beginning. But he also said that he believes his film dovetails nicely with the privacy concerns raised by NSA leaker Edward Snowden and will help people better understand what, exactly, they’re consenting to when they hit the “I agree” button.

(Washington Post Co. chairman and chief executive Donald E. Graham is a member of Facebook’s board of directors.)

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