Should Feinstein be investigated and/or charged for withholding Ford's letter from the committee until the very last moment?

Should Feinstein be investigated and/or charged for withholding Ford's letter from the committee until the very last moment?

Nope because it doesn't matter. Unethical repubs are going to ram this confirmation through anyway. Kav isn't on trial here, it's just a character study, and McConnell doesn't care a whit about character.

Her Chinese chauffeur spy is the bigger reason.

Yes

According to Feinstein, she withheld it at Prof Ford's request. After it was leaked, Feinstein got permission to officially release the letter.
So, no - we're trying to be a democracy - we don't charge people just because they're in the opposition party, trying to do their job.

Charged for what, making regressives cry is not a crime.

YES

No. There's no rule or law which requires Senators to hand over information in a timely manner, we're in a way which would be most helpful to the majority.

Weather Feinstein link to the accusation to the media is another story. However, the reporter who broke the story has said that Dianne Feinstein or anyone in her office was the source of his story

Yes.
If a Republican Senator had Ford's letter and withheld it until the last moment like Feinstein did, Democrats would be screaming about obstruction and conspiracy.

Yes, she should.

Not a crime