Sen. Dianne Feinstein (D-California) unilaterally released the more than 300-page congressional testimony of Fusion GPS founder Glenn SimpsonDonald Trump responded with a criticizing tweet.

Glenn Simpson’s Fusion GPS Testimony

Simpson, a former newspaper reporter and founder of the research firm Fusion GPS, spoke to the Senate Judiciary Committee for more than 10 hours last August and told of his findings on Trump. Simpson shared that he and his associate, former British intelligence operative Christopher Steele, had found evidence that Trump had coordinated with the Russians to manipulate the 2016 presidential election.

Simpson testified that the FBI had reason to believe Steele’s intelligence, and shared that the bureau had a walk-in from someone in Trump’s inner circle. Other sources, however, say that Simpson conflated what he had been told. Simpson also told of a dossier, which had unverified allegations that Russia had been grooming Trump for the presidency for years and had gathered information on Trump for blackmail. That dossier was published by Buzzfeed in January 2017.

GOP senators did not want Simpsons August testimony released, but Feinstein decided to make it public on her own. In his tweet, the president called the senator “Sneaky” and asserted that releasing the document could be illegal – Simpsons testimony, however, was unclassified, so her move was legal.

“The fact that Sneaky Dianne Feinstein, who has on numerous occasions stated that collusion between Trump/Russia has not been found, would release testimony in such an underhanded and possibly illegal way, totally without authorization, is a disgrace. Must have tough Primary!” the president said.

Feinstein, who faces re-election this year, has not responded to Trump’s tweet.