Several senators left Twitter’s private briefing with United States congressional investigators unimpressed.
Democratic Senator Adam Schiff told reporters on Thursday that Twitter had taken no more than remedial steps to combat accounts linked to Russian government actors, and still has work to do.
“We look forward to hearing more from Twitter as we continue to investigate how Russia sought to push disinformation and fake news through the use of bots and false personas to influence the outcome of the election,” said Schiff said in a statement after Twitter executives met with the committee.
In addition, top Democrat on the Senate intelligence panel, Senator Mark Warner, told reporters that the meeting was “deeply disappointing,” and that “their response was, frankly, inadequate on almost every level.”
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A day earlier, House and Senate intelligence committees asked executives from major technology firms, including Alphabet’s Google, Facebook and Twitter to testify at a public hearing on Nov. 1 about alleged Russian interference with the 2016 American presidential election.
Warner, whose panel is investigating these potential breaches, said that Twitter officials had sparsely answered questions about the Russian use of the platform and that it was still subject to “foreign manipulation.”
As part of an ongoing congressional investigation, lawmakers are concerned that social networks may have played a key role in the spread of fake news and disinformation by Moscow during the 2016 election, as part of attempts to help elect U.S. President Donald Trump.
Thus far, Trump and his administration have denied all accusations of collusion with the Russian government.
Thursday’s closed-door briefing between Twitter executives and senators follows similar meetings with Facebook earlier this month. Facebook has taken a different approach to addressing claims that its platform may have contributed to sewing discord in months leading up to Trump’s election.
While Facebook has rolled out several new initiatives to address transparency issues around fake news and political advertising, Twitter has remained relatively quiet.
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“They have obviously a different business model, and also they’ve never tried to prevent fake accounts, use of bots,” Warner told the Associated Press, comparing the company to Facebook. “They don’t deny they have allowed more anonymity. So they’ve got a different business model, we’ve got different questions for them.”
In a statement released last week, Twitter confirmed that it would meet privately with congressional investigators to discuss the use of its platform during the election.
“Twitter deeply respects the integrity of the election process, a cornerstone of all democracies, and will continue to strengthen our platform against bots and other forms of manipulation that violate our Terms of Service,” read the statement.
Neither Twitter, nor Google or Facebook has confirmed whether they will accept invitations to testify publicly on Nov. 1.
-With files from Reuters.
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