Foreign Policy is reporting exclusively that President Trump "pressed senior aides last June to devise and carry out a campaign to discredit senior FBI officials after learning that those specific employees were likely to be witnesses against him as part of special counsel Robert Mueller’s investigation."
When former FBI director James Comey testified before the Senate Intelligence Committee on June 8, 2017, he told the panel he had discussed Trump's alleged efforts to stop the Russia investigation with other senior officials at the time. Newly hired Trump lawyer, John Dowd, reportedly told Trump this would be a problem.
FP:
Dowd warned Trump that the potential corroborative testimony of the senior FBI officials in Comey’s account would likely play a central role in the special counsel’s final conclusion, according to people familiar with the matter.
In discussions with at least two senior White House officials, Trump repeated what Dowd had told him to emphasize why he and his supporters had to “fight back harder,” in the words of one of these officials.
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Since Dowd gave him that information, Trump — as well as his aides, surrogates, and some Republican members of Congress — has engaged in an unprecedented campaign to discredit specific senior bureau officials and the FBI as an institution.
The FBI officials Trump has targeted are Andrew McCabe, the current deputy FBI director and who was briefly acting FBI director after Comey’s firing; Jim Rybicki, Comey’s chief of staff and senior counselor; and James Baker, formerly the FBI’s general counsel. Those same three officials were first identified as possible corroborating witnesses for Comey in a June 7 article in Vox. Comey confirmed in congressional testimony the following day that he confided in the three men.
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[Special Counsel Robert] Mueller has asked senior members of the administration questions in recent months indicating that prosecutors might consider Trump’s actions also to be an effort to intimidate government officials — in this case FBI officials — from testifying against him.
Full story: Trump Launched Campaign to Discredit Potential FBI Witnesses (Foreign Policy)