Last Updated Oct 31, 2018 1:25 PM EDT

Members of the U.K. and Canadian Parliaments will hold an unprecedented joint "international grand committee" scrutinizing disinformation and online election influence campaigns, and they want Facebook CEO Mark Zuckerberg to appear in person.
In a letter sent Wednesday to Zuckerberg and released to the public, the British and Canadian committee chairs chastised the Facebook founder for ignoring previous invitations to appear at their separate inquiries.
"You have chosen instead to send less senior representatives, and have not yourself appeared, despite having taken up invitations from the US Congress and Senate, and the European Parliament," wrote Damian Collins, Chair of the U.K. Digital, Culture, Media and Sport Select Committee, and Bob Zimmer, Chair of the Canadian Standing Committee on Access to Information, Privacy and Ethics.
"No such joint hearing has ever been held. Given your self-declared objective to 'fix' Facebook, and to prevent the platform's malign use in world affairs and democratic process, we would like to give you the chance to appear at this hearing," they wrote.
The hearing is scheduled for Nov. 27 in London. Collins and Zimmer ask in the letter for Zuckerberg to reply by Nov. 7. In a statement to CBS News, a Facebook spokesperson said the company has "received the committee's letter and will respond to Mr. Collins by his deadline."
During an Oct. 2 phone call with CBS News, Zimmer said American politics has prevented the Senate's investigations of election interference from being as aggressive as those of the Parliaments.
"We don't have Citizens United and all the money and outside influence that comes with that," Zimmer said. "We're mostly average Janes and Joes who are interested in the truth."
While questioning witnesses, Zimmer's committee has frequently referred to a*scathing preliminary report*on "disinformation and fake news" written by Collins' committee in July. It called for increased oversight of social media companies and election campaigns, while highlighting the use of "scraped" Facebook data by companies associated with the successful "Brexit" campaigns and President Trump's 2016 run.
The report, by the House of Commons' Culture, Media and Sport, claimed social media and mass data collection created a crisis for democracies, It said campaigns could engage in "relentless targeting of hyper-partisan views, which play to the fears and prejudices of people, in order to influence their voting plans and their behaviour."
The U.K.'s investigation has sought to shine light on the use of intimate personality datasets on more than 80 million people as part of advertising campaigns surrounding the so-called "Brexit" campaigns, and Donald Trump's presidential run. The campaigns were run by a British company called SCL Elections, its American affiliate Cambridge Analytica, and a Canadian company called Aggregate IQ.
The Canadian investigation has honed in on Aggregate IQ. The company's Chief Operating Officer and CEO have each appeared before Canadian Parliament to testify about the company's involvement with Brexit campaigns. During a Sept. 27 hearing, CEO Zackary Massingham was directly accused of lying to Canadian Parliament about his company's work, while other members of Parliament wondered aloud if he was lying or obfuscating.
Both the Canadian and British committees plan to release final reports in December, which is why Zimmer and Collins said in the letter the need for Zuckerberg's testimony is "overdue, and urgent."


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