U.S. Rep. Rob Woodall and challenger Shane Hazel clashed in a GOP primary debate in Cumming Thursday over illegal immigration and Robert Mueller’s investigation of Russian meddling in the 2016 presidential election.

Asked about Mueller’s probe, Woodall, who represents parts of Gwinnett and Forsyth counties, said he supports “getting to the bottom so that folks don’t have any questions at all about who did what to whom and when did they do it.” Woodall then turned to the allegations swirling around Donald Trump’s presidential campaign.

“It offends me the way the president has been maligned for what folks have shown absolutely no proof of whatsoever,” the Lawrenceville Republican told a packed audience at the Forsyth County Administration Building. “We have had the best lawyers in the business trying to catch him on it. And they failed. We finished our investigation in the House — terminated it with no finding of wrongdoing. And it is coming time for Mr. Mueller to do the same.”

A Marine Corps veteran, Hazel went a step further.

“Collusion like they have talked about is not a crime in the first place and so it should be dismissed and Mueller should probably be terminated at the president’s discretion,” Hazel said. “He is the boss indeed.”

The two candidates also differed over how to stop illegal immigration.

Woodall emphasized border security.

“You can’t move immigration reform forward without doing border security because you just trap another family in that same space tomorrow. But the president has offered a negotiated bargain. It wouldn’t have been the one I’d propose. But I support him and I believe we can get it done this year,” Woodall said.

Hazel proposed cutting off welfare for unauthorized immigrants – they already are ineligible for most federal public benefit programs – and bringing U.S. troops home from conflicts abroad and putting them to work securing the southwest border with Mexico.

“Shut off the welfare magnet. Period. No illegals get welfare from the United States. That will start pushing them back right there,” he said, eliciting applause. “We can bring our troops home and secure the southern border really quick.”