Former Acting Attorney General Matthew Whitaker backed Sen. Lindsey Graham’s assertion that the House Democrats’ impeachment inquiry will be “dead on arrival” if it’s not conducted fairly before it reaches the Senate.

“Not only is it dead on arrival, there’s a risk that the Senate doesn’t even take it up as it is a completely partisan exercise where [there are] only Democrat witnesses, only Democrats’ votes, and Republicans’ rights to due process and fairness are not honored,” Whitaker told “Outnumbered Overtime.”

Graham, R-S.C., accused House Intelligence Committee Chairman Adam Schiff, D-Calif., of not caring about the truth, and said Schiff’s impeachment efforts would go nowhere unless he called the anonymous whistleblower to come forward and testify about the complaint against President Trump.

SEN. GRAHAM: IMPEACHMENT 'DEAD ON ARRIVAL' IN SENATE IF DEMS KEEP WHISTLEBLOWER FROM TESTIFYING

House Republicans over the weekend submitted a list of witnesses they wanted to call for public testimony during the impeachment inquiry, but Schiff was swift to reject the request to have the whistleblower come forward.

If the House inquiry were to result in Trump being impeached, the matter would then go to a trial before the Senate, which Graham said would be doomed if the whistleblower did not come forward.

DEM LEADER TELLS GOP TO 'GET LOST' OVER IMPEACHMENT INQUIRY WITNESS LIST

“It’s impossible to bring this case forward, in my view, fairly, without us knowing who the whistleblower is and having a chance to cross-examine them about any biases they may have,” he said. “So, if they don’t call the whistleblower in the House, this thing is dead on arrival in the Senate.”

Democrats have claimed the whistleblower's testimony was irrelevant because the witnesses who already have testified provided more information than the whistleblower would have regarding Trump's July 25 phone call with Ukrainian President Volodymyr Zelensky, a call at the heart of the inquiry.

CLICK HERE TO GET THE FOX NEWS APP

Whitaker said there were other issues Congress needed to address other than the impeachment inquiry.

Fox News' Ronn Blitzer contributed to this report.