Senate investigators now have the specific profile names or "handles" of the 201 Russia-linked accounts Twitter uncovered and shut down at the end of September, but it is unclear whether Twitter still has the tweets pushed out by those accounts.
Politico explains that Twitter's strong pro-consumer privacy policies say that when a user deletes content so will the company. And because Russian cyber operatives are trained to leave no clues, experts assume any remaining content has been left behind on purpose to throw investigators off track.
Thomas Rid, a Johns Hopkins University Strategic Studies professor and expert witness for the Senate Intelligence Committee tells Politico:
"Were Twitter a contractor for the FSB,” the Russian intelligence agency involved in the 2016 campaign to meddle in the U.S. election, "they could not have built a more effective disinformation platform.”
Twitter deleted data potentially crucial to Russia probes (Politico)