Go back and read how the Anita Hill accusation was confidential until it leaked....AFTER the White House had authorized the FBI to investigate and add to their background of Clarence Thomas.
Affidavit done in mid September.
FBI investigation complete Sept 27, 1991.
Outing of her accusations in the news on Oct. 6.
Her story was known to senators when they voted to send confirmation to the full senate (thought the lead democrat initially said he had not seen it). Biden made sure they all knew and took back documents after they were shared to keep it confidential in respect to Anita Hill's wish to remain private.
Feinstein surely knew that she could have asked for and presented an affidavit to the committee and the committee could have then agreed to further background investigation by the FBI, as they had done before. But she did not do that. She waited on it until nearly the last possible moment. Even then, she would not immediately share the letter.with the other senators.
Ford would have written the letter for the same reason Hill gave her testimony....for the judicial committee to have the info, but to remain anonymous to the public. But Feinstein did not share it in confidential quarters, even though she had no idea at the time if it could be corroborated or not.
. (the Hill leak came as she tried to find out if the committee had seen her affidavit before their initial vote. Her message had passed to too many people)
If Ford has valid information on the candidate that would have changed the nomination process, then she has been used and abused by Feinstein for political theater. There was clearly another, earlier, and much more private way to handle it.