Mark Zuckerberg tells Congress it's a 'conspiracy theory' that Facebook uses your microphone to spy on you

For years, Facebook users have publicly speculated the the app might be spying on them through their smartphone's microphone, using their conversations to target unbelievably specific ads.

"My understanding is that a lot of these cases that you’re talking about are a coincidence," Facebook CEO Mark Zuckerberg told Congress on Wednesday. He said that Facebook does not listen to unauthorized audio, and claimed that he isn't aware of any similar tech company that does.

It was actually the second time that Zuckerberg had to deny the practice in as many days: On Tuesday, Zuckerberg told a joint session of the Senate that it was a "conspiracy theory," and denied the practice with a flat "no."

Facebook itself has regularly denied it does this since at least 2014.

Congressman Bucshon pushed Zuckerberg on the matter on Wednesday, and shared instances from his person life in which he or his family members had been served ads that he felt were suspiciously based on verbal conversations they had offline. Zuckerberg said that there was a more innocent explanation.

"Someone might be talking about something, but then they also go to a website or interact with it on Facebook because they were talking about it, and maybe they’ll see the ad because of that," Zuckerberg explained.

The only time Facebook records audio, Zuckerberg said on Tuesday, is when a user records a video. And that audio is not used for targeting ads, he says.

More on Zuckerbergs blockbuster hearing:

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