A conservative activist has filed an ethics complaint against what she says is a dark money organization backing the Republican candidate for lieutenant governor.

Debbie Dooley, an early tea party organizer in the state, said Georgia Swamp Drainers violated state law by not reporting that it spent tens of thousands of dollars in support of GOP lieutenant governor nominee Geoff Duncan and defeated gubernatorial candidate Casey Cagle during the July Republican runoff campaign.

“From the mailers paid for by Swamp, it is apparent that more than $25,000 was expended by Swamp advocating for the election and defeat of candidates and that potentially hundreds of thousands of dollars were expended for this purpose,” Dooley says in the complaint.

Groups spending money to influence political campaigns are required to register and file reports. Georgia Swamp Drainers is not registered as a state political action committee or independent committee. It also isn’t registered as a business or charity in the state, according to the Secretary of State’s Office’s website.

Some groups are called "dark money" organizations because they spend money on campaigns but won't disclose where their money comes from. As The Atlanta Journal-Constitution reported in July, such groups are playing an increasing role in state politics.

“This is not going after Geoff Duncan, this is going after that dark money group,” Dooley told the AJC on Thursday. “This is important because who knows, if these groups get away with these tactics, they’ll probably use it in the general election, too.”

Duncan’s campaign denied any connection to the mailers.

Dooley is asking the state ethics commission to refer the complaint to the Gwinnett County District Attorney’s Office to investigate and pursue any charges.

“This ‘dark money’ operation has already corrupted the electoral process and affected the outcome of at least one statewide election,” Dooley said in the complaint.

This is not the first time a dark money group has been accused of helping Duncan win the runoff.

The Washington-based Hometown Freedom Action Network spent millions of dollars in support of the Cumming Republican during the primary and runoff. The group received most of its donations from Citizens for a Working America and reported about $3 million in contributions to spend against Duncan's opponent, state Sen. David Shafer.

Duncan's campaign acknowledged that campaign mailers and commercials paid for by outside groups likely helped lift the candidate to a narrow victory last month.

Dooley says a mailer sent by Georgia Swamp Drainers alleged that it was the "Official Trump Voter Guide," falsely stating that President Donald Trump endorsed Duncan and Cagle.

Trump endorsed Cagle’s opponent, Secretary of State Brian Kemp, who went on to win the runoff last month. Trump did not endorse a candidate in the lieutenant governor’s race.

The return address for the “voter guide” is the same as Printing Trade Co. in Norcross, Dooley says in her complaint, which is next door to AGCO Inc., a countertop manufacturer where Duncan is a consultant.

“Geoff Duncan is also the primary beneficiary of the illegal expenditures and communications made by Swamp,” Dooley wrote in her complaint. “Geoff Duncan may know the identity of the individuals operating Swamp.”

Duncan campaign spokesman Dan McLagan denied the candidate knew anything about the source of mailers.

"We have no idea who this group is, but I do note that there are a lot of politically connected businesses adjacent to the group she is accusing of skulduggery — including a number of David Shafer's companies and others the AJC has recently reported on," McLagan said. "Obviously, David did not attack himself, but it shows that you can't swing a possum around there without hitting a political group. Maybe we need Inspector Clouseau on the case."

Dooley said she hopes her complaint will stop the “corrupting influence” on future elections.

“It’s like cockroaches,” she said. “You shine the light on groups like this and the rest of them scatter.”

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