(From the link I posted which you apparently refuse to read)
There have always been indications that the operation went far beyond the FBI, however. For example, former CIA director John Brennan, now an MSNBC contributor, separately briefed Sen. Harry Reid, (D-Nev.) about the operation. Reid understood that move was undertaken so he could publicize the Russia investigation to influence the ongoing presidential election campaign.
Former director of national intelligence James Clapper, now a CNN contributor, admitted to discussions with media outlets about the investigation. The U.S. embassy in London was used contrary to established protocol to funnel hearsay that was used as a pretext to officially launch a wide-ranging investigation against the entire Trump orbit. Clinton-connected officials in the State Department were also used to disseminate unverified gossip and allegations about Trump throughout the federal government.
The use of covert individuals to surreptitiously obtain information on private American citizens and share it with the government is the most obvious publicly known indication that agencies beyond the FBI may have been intimately involved in the operation. It is clearly possible that every single instance of intelligence collection was done entirely by the FBI without any assistance from any other federal intelligence agency. However, that has not been determined by any investigative body.
The use of Stefan Halper, for example, a London-based American academic with longstanding ties to the FBI, CIA, and Defense Department, raises serious questions about whether CIA assets or resources were used against American citizens. Following Nixon-era domestic spying abuses by the U.S. intelligence community, oversight bodies
restricted the authority of the CIA to spy on U.S. citizens on U.S. soil.
