Nunes Memo notes

Christopher Steele, the alleged saint behind the dossier, was
terminated by the FBI because he "improperly concealed [evidence] from
and lied to the FBI." And his credibility was the primary basis for a
wiretap on an American citizen.

http://thehill.com/opinion/criminal-justice/371853-new-fbi-messages-reveal-agents-searching-for-way-to-evade-record

FBI takes "salacious and unverified" dossier to secret court to get
secret warrant to spy on a fellow American, and FBI doesn't tell the
court that the DNC/Clinton campaign paid for that dossier. And they
did that FOUR times.

Each FISA renewals have to have probable cause. Rod Rosenstein, Sally
Yates and Jim Comey all signed FISA renewals without any probable
cause or concrete evidence.

It is important for the American public to know if the dossier was
paid for by another candidate, used in court pleadings, vetted before
it was used, vetted after it was used, and whether all relevant facts
were shared with the tribunal approving of the FISA application.