"The Democratic Caucus has gathered here today to essentially state a silent protest. We will attend meetings, we will question assiduously, but we want to express our concerns," Feinstein told reporters. "I’ve never had a hearing like this, where documents are so difficult to get."
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The Democrats have sent a letter to White House Counsel Don McGahn demanding that all documents related to Kavanaugh be turned over to the committee immediately, Feinstein added.
Kavanaugh's confirmation hearings start on Tuesday and are expected to last the rest of the week.
US President Donald Trump announced the nomination of Kavanaugh on July 9 to replace Justice Anthony Kennedy, who stepped down from the high court.