Rep. Chris Stewart (R-Utah) agreed with Rep. Sean Maloney's (D-N.Y.) call for the State Department to comply with the House impeachment inquiry's subpoena on ABC's "This Week," but only if Democrats agree to bring in the whistleblower to testify.

The exchange:

MALONEY: Chris, will you join me in calling on the State Department to produce the mountain of evidence. Emails, notes, call records, calendar entries. They could produce that tomorrow. Our committee has subpoenaed them. Will you join me in calling on the State Department to produce the evidence?

STEWART: You bet. I don't think there's anything there that is going to implicate the president. If, Sean, you will join with me in calling to hear from the whistleblower. We can protect his anonymity. We can protect him. How in the world can you impeach the president of the United States and never hear from the person who started that process? We know he was deeply involved in this. How can you say that we don't need to hear from him?

Why it matters: One of the core impeachment defenses used by President Trump and his Republican allies has been that none of the witnesses who have testified thus far have firsthand evidence corroborating the allegations. However, as Maloney pointed out, the Trump administration has defied subpoenas for records and refused to allow officials who discussed Ukraine directly with the president to testify.

On Stewart's call for the whistleblower to testify, Maloney countered that President Trump has accused them of treason, and that the law requires the government to protect whistleblowers from retaliation.

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