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Twitter Reportedly Deleted Tweets Valuable to Russia Probe Because of Its Privacy Policy

October 13, 2017, 5:47 PM UTC

Twitter’s privacy policies could prove frustrating to the lawmakers investigating Russia’s alleged campaign to influence last year’s presidential election.

According to Politico, the social media service deleted tweets and other user information “of potentially irreplaceable value” to federal officials probing Russia’s interference with the U.S. electoral process.

Politico’s report, which cites anonymous current and former government cybersecurity officials, notes that Twitter’s own privacy policies require the company to delete any information from tweets or accounts that have themselves been deleted or revised. Meanwhile, U.S. intelligence officials believe that Russian-linked accounts on widely-used services like Twitter, Facebook, and Google’s YouTube spread reams of misinformation aimed at disrupting last year’s election through the use of automated bots and other fake accounts.

Investigators believe that the purpose of the Russian interference was to help boost Donald Trump’s chances of winning the 2016 election, Politico reports. And, with Twitter having deleted relevant tweets and other information from accounts linked to that Russian campaign, that potentially valuable information is now likely lost forever, the anonymous officials told Politico.

Twitter’s own data retention guidelines, published online, note that “once an account has been deactivated, there is a very brief period in which we may be able to access account information, including Tweets . . . Content deleted by account holders (e.g., Tweets) is generally not available.”

Thomas Rid, an expert witness for the Senate Intelligence Committee’s Russia probe, told Politico that he believes it’s a “scandal” that Twitter allows “bot operators and people who spread hate and abuse” to then remove that content from public view. “It removes forensic evidence from the public domain, and makes the work of investigators more difficult and maybe impossible,” he said.

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Fortune contacted Twitter and we will update this article with any response.

Last month, Twitter officials met with Congress to discuss how Russian-linked Twitter accounts may have been used to influence the 2016 election. However, some lawmakers described those meetings as “disappointing” and “inadequate” while accusing Twitter of ignoring large amounts of evidence of disruptive Russian activity. At some point this month, officials from Twitter, Facebook, and Google-parent Alphabet are all expected to testify publicly before Congress on the issue.