Sen. Brian Schatz, D-Hawaii, was visibly troubled after reviewing the FBI report on sexual allegations against Supreme Court nominee Brett Kavanaugh on Thursday, calling the investigation a "joke."

"I love the Senate, and I’ve never been so appalled at this institution," Schatz told reporters moments after leaving the secured room where the single copy of the report is being held.

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Republicans have said there is no corroborating evidence to support Christine Blasey Ford, who alleges Kavanaugh assaulted her while they were in high school. Schatz pushed back.

"All of our worst fears about this being incomplete in the extreme have been justified," Schatz said. "If you don't interview people, provided by counsel for the accusers, who say they can corroborate and then you say our interview process provided no corroboration, it's a joke."

"It's like you lose your keys in your apartment, and you only look on the bathroom floor, and you decide your keys are gone," Schatz added.

The normally upbeat Schatz expressed great frustration with the report and the state of the upper chamber.

"All I will say is that this institution is at a low ebb," said Schatz.

[Related: Bob Menendez calls FBI’s Brett Kavanaugh report a ‘bullshit investigation’]