Republicans on the House Oversight and Reform Committee "dropped the ball" on defending President Trump during Michael Cohen's public testimony on Capitol Hill Wednesday, according to Chris Christie.

The former New Jersey governor and 2016 Republican presidential candidate joined the "Fox & Friends" co-hosts in front of a live studio audience Friday to give his key takeaways from Cohen's testimony.

Cohen, Trump's former longtime attorney and fixer, was sentenced to three years in prison after he pleaded guilty in November to campaign finance violations, tax evasion and lying to Congress about Trump’s past business dealings in Russia.

Christie noted that numerous Republicans used their time during Wednesday's hearing to cast doubt on Cohen's testimony by reiterating that he had already pleaded guilty to lying to Congress.

He said once two or three lawmakers had established that Cohen is not a credible witness, they should have moved on to the substance of Cohen's testimony and his corroborating evidence.

"I wish that our Republicans in Congress would have defended the president substantively," Christie said.

He explained that they could have highlighted that Cohen's testimony supports the argument that alleged hush money payments to women who allege affairs with Trump did not represent criminal wrongdoing on the president's behalf, and that Trump never directed Cohen to lie to Congress.

"We, as Republicans, need to defend the president on the substance. That's what we need to be doing," Christie said. "And they dropped the ball on the president. And I'm sure he wasn't very happy about it in Vietnam."

Watch the "Fox & Friends" interview above.

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