A Republican lawmaker says he believes Speaker Glen Casada was "willing to rig" a House Ethics Committee proceeding this week and is calling for his resignation.

Rep. Mike Carter, R-Ooltewah, released a lengthy statement to the Chattanooga Times Free Press on Thursday night describing how he was disturbed that he and other members of the ethics committee were asked to sign an advisory opinion that "would be used as an exoneration of the Speaker's conduct," despite raising questions about statements of fact Casada had submitted.

Carter described it as "the final straw" in withdrawing his support for Casada. Carter is now one of 10 House Republicans who have called for the speaker to step down amid a scandal involving racist and misogynistic text messages.

Carter said he was informed that Casada, R-Franklin, would not swear under oath that the facts submitted — which Carter believed "did not appear to be in line with the documents existing in the public realm" — were true and correct.

"In my six years on the ethics panel this is wholly without precedent," said Carter, a former Hamilton County General Sessions Court judge. "If the requestor is willing to rig and predetermine an outcome of the ethics committee this week he is in my opinion ... not fit to hold the trust of his office or the state of Tennessee."

Carter, along with several Democratic members of the 10-member committee, met Monday with Deputy Speaker Matthew Hill, R-Jonesborough.

He said after reviewing the statement of facts — which presumably pertained to the text message scandal — Hill asked him to sign a letter stating that the committee had found Casada committed no ethical violations.

Hill previously reported that the committee was meeting in response to Casada's request for an advisory opinion about his handling of the resignation of his former chief of staff Cade Cothren.

Carter said he declined to sign the letter without Casada affirming under oath that the information was true, or without amending the committee's advisory opinion to reflect that "the facts upon which the opinion was rendered appear to be divergent from facts in the public record," he said.

The ethics committee meeting scheduled for later Monday afternoon was ultimately canceled after the chief clerk determined the committee should have provided public notice days ahead of the gathering.

In a statement Friday, Casada defended the integrity of the ethics committee process and vowed he had not seen the letter in question.

"I believe the process is fair and allows for a committee composed equally of Republicans and Democrats to review a situation and offer their guidance," Casada said. "I have not seen any of the work completed by the Ethics Committee, and I await their final determination."

Caucus chairman says he also would decline to sign letter without sworn statement of facts

House Republican Caucus Chairman Cameron Sexton, R-Crossville, said he did not meet individually with Hill on Monday morning, but would also have declined to sign the advisory opinion without Casada swearing to the facts he submitted about the ongoing scandal.

"My gut tells me I would agree with Judge Carter that (the facts) would need to be given as a sworn statement," said Sexton, another committee member. "If they weren't, then I wouldn't have voted to adopt the letter."

Sexton also questioned why the committee was asked to give an opinion on the speaker's involvement in Cothren's resignation, since it was not a firing.

"When someone resigns, I'm not sure what you would be looking at in an investigation," Sexton said.

"I don’t even understand why that would be brought to the committee in the first place."

Sexton, who will facilitate a caucus meeting Monday where a vote of confidence may be taken, has not called on Casada to resign.

Carter says ethics committee stunt 'the final straw' in Casada support

Carter described the recent proceeding involving the ethics committee as something he had never seen before.

"My concern with the meeting is that it shows a heart for misrepresentation and political maneuvering to save the requestor’s office even at a loss of reputation and integrity of the House Ethics Committee," Carter said.

He elaborated that while text messages sent by Casada and Cothren were concerning, along with Cothren's admission to using cocaine in the legislative office building, the recent events surrounding the ethics committee were more disturbing.

"I could argue that the text messages are disqualifying," Carter said. "I could argue that knowing and failing to report felony criminal conduct in his presence is disqualifying. I could argue that spending $7 million to operate his office more than Speaker Beth Harwell is disqualifying, but respectfully I state that attempting to pre-determine an opinion from the Ethics Committee is the final straw for me."

In a statement, Hill said that no formal document had been introduced as part of the full committee, and maintained that he had received input from committee members on Monday and in recent days as he continues to formulate the final advisory opinion.

"The Speaker has not seen any of the work compiled by the Ethics Committee or legal services at this point, and he has also not been asked to sign any document under oath," Hill said.

Reach Natalie Allison at nallison@tennessean.com. Follow her on Twitter at @natalie_allison.

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