House Judiciary Committee chairman Rep. Jerry Nadler (D-NY) argued on Sunday’s broadcast of CBS’s “Face the Nation” that Republican senators who wanted to negotiate on witnesses were “part of the coverup.”

Partial transcript as follows:

MARGARET BRENNAN: OK. Well, on the question of witnesses, from what we are hearing from Senate Republicans, there will eventually be a vote on whether or not to hear from witnesses. Not a commitment upfront, but an agreement to talk about it and vote on it later. Is there any circumstance in which Democrats would consider, for reciprocity, having Hunter Biden come and testify?

NADLER: You know, the question of witnesses in any trial, in any trial, all relevant witnesses must be heard. Whether if- if you’re accused of robbing a bank, testi- testimony that I saw him rob the bank or he was somewhere else, he couldn’t have robbed the bank, is admissible. It’s not negotiable whether you have witnesses. And this whole controversy about whether there should be witnesses is just- is really a question of does the Senate want to have a fair trial or do they- or are they part of the cover up of the president? Any Republican senator who says there should be no witnesses or even that witnesses should be negotiated is part of the cover up.

BRENNAN: So, you’re saying no way would Hunter Biden ever be called to testify?

NADLER: Well, I’m saying that Hunter Biden has no knowledge of the accusations against the president. Did the president, as we said- as the evidence shows that he did, betray his country by conspiring with a foreign country to- to try to rig the election? Hunter Biden has nothing to say about that. They’re- they’re asking for Hunter Biden is just more of a smear of Hunter Biden that the president’s trying to get the Ukraine to do. But the fact of the matter is, let the chief justice rule on- on–

BRENNAN: Well–

NADLER: –the chief justice in the first instance rules on evidence. The Senate can overrule him.

BRENNAN: Yeah.

NADLER: But no chief justice would- would- would think of- of admitting evidence that- that is not relevant.