With a handful of reporters and a few supporters watching on, the state senator accused Cagle of thwarting his proposal to boost pay for police. And he again asserted that Cagle and his allies offered him a plum position to drop his campaign.
Pressed after his roughly 7-minute speech about delivering the promised evidence, Williams came up empty.
At one point, he said the fact that he could only convince two other GOP senators to co-sponsor his police-pay legislation was proof of Cagle's interference, saying he based that on "comments they made to me." He would say nothing else.
When asked for verifiable details about his claim that he was offered a powerful committee chairmanship to back out of the governor's race, he repeatedly refused comment.
"In time," he said.
From the back of the room, Cagle aide Brian Robinson jumped in: "Now's a good time."
Williams, seeming flustered, was peppered with several more questions about backing up his claims, each time saying he would not do so.
"We have a very long race ahead of us," he said.
Williams is centering his campaign on his loyalty to Donald Trump - he was the first state elected official in Georgia to endorse him - and he's tried to steal a page from his playbook with one headline-grabbing accusation after another.
Williams also made a string of blunders, including a much-distributed picture he took in June with a controversial militia and a rocky interview with CNN where he struggled to answer questions on the GOP healthcare bill.
Though he's run an in-your-face campaign, he's no fringe candidate. He's twice been elected to a state Senate seat in deep-red Forsyth County, and he's already pumped $1 million of his own fortune into the campaign to bolster the paltry $50,000 he's raised.
The event on Thursday touched on an early flash-point in the governor's race. Cagle said last week he was exploring the idea of setting a new minimum wage for police officers, months after Williams pushed a similar proposal that failed to gain traction.
But the circus-like spectacle of the event - Cagle staffers briefly considering hiring clowns to interrupt the press conference - evoked memories of the last time a GOP candidate for governor advertised a "major" press conference outside his top rival's office.
Former Dalton Mayor David Pennington's 2014 event, just a few feet from Gov. Nathan Deal's second-floor statehouse digs, featured a hand-lettered sign, snickering Deal staffers and a made-for-TV interruption from the governor's attorney - who ended up speaking longer than Pennington.
Thursday's event delivered a similar scene: A small group of reporters flanked by a wider ring of Capitol staffers and campaign deputies curious about Williams' threat to unleash Cagle's "previously undisclosed actions."
After the event, as Williams quickly disappeared and head-shaking staffers returned to their offices, state Sen. Renee Unterman stayed behind. In unsparing terms, she accused Williams of running a "fraudulent" campaign and of playing bait-and-switch with overhyped promises.
"He wants to lead the voters on and the media on," said Unterman, who backs Cagle. "It's fluff. And it's not very good fluff."
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