Editor's note: This story has been updated throughout.

The Texas Ethics Commission on Thursday voted to end a long-running investigation into one of the state's most influential conservative groups.

By a vote of 7-0, the commission dismissed a pair of years-old complaints against Empower Texans, a politically active nonprofit that does not have to disclose its donors. Former state representative Steve Wolens, a new member of the eight-person panel, recused himself.

The commission said the complaints were being thrown out "on the basis that there is insufficient credible evidence" to support them. The panel reached the decision after deliberating in private for about 20 minutes.

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The vote could signal a new chapter for the panel, a perennial target of conservative critics claiming it wants to violate their First Amendment rights. For years, members had sought to get information out of Empower Texans that could shine light on its political activities, with the group — and its leader, Michael Quinn Sullivan — resisting at every turn.

After the vote, Sullivan vowed to "keep fighting" against the commission. Sullivan's lawyer, Joe Nixon, said he has "filed a civil rights case" against the panel for putting his client through the four-year process that started with the complaints by two state representatives.

"I think that we’ve now turned a corner in which we’re showing the ethics commission that they’re going to find out what real punishment looks like," Sullivan said, speaking alongside Nixon outside the hearing. "When you go out and try to violate people’s civil liberties, you don’t get away with it, despite what they and their political masters in the Texas House have wanted to do."

The decision Thursday came a time of transition for the commission. Under pressure from conservative activists, state leaders have started dealing with so-called "holdovers" on the panel, or members serving after their terms have expired. Earlier this month, Gov. Greg Abbott made two appointments to the commission, Chad Craycraft and Katie Kennedy, to replace holdovers. 

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