'Immoral, unethical... illegal': Witness directly links Ken Paxton's affair to abuse of office
(Credit: Mark Felix for The Texas Tribune)

A former assistant to Texas Attorney General Ken Paxton testified on Wednesday why he believed his then-boss' affair with a woman was "relevant" to impeachment proceedings.

Jeff Mateer, a former first assistant in the Texas Attorney General's Office, was first to take the stand in Paxton's state Senate impeachment trial.

Mateer told the Senate that he had not understood Paxton's favors for businessman Nate Paul until the attorney general revealed his extramarital affair during an office meeting. Mateer said he learned that Paul had hired the woman engaged in the affair with Paxton.

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"Because it answered one of the questions that I kept struggling with is, why would General Paxton jeopardize all this great work that we had been doing in the Office of Attorney General?" Mateer said. "It answered the question, why is he engaging in all these activities?"

"I mean, it seemed to me he was under undue influence," he added. "At times, I thought, is he being blackmailed?"

Mateer said he eventually took his concerns about abuse of power to the FBI.

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"By that time, I concluded that Mr. Paxton was engaged in conduct that was immoral, unethical, and I had a good faith belief that it was illegal," he remarked.

Watch the video from WFAA below or at this link.