Florida Gov. Ron DeSantis escalated his hostilities with former President Donald J. Trump on Friday, claiming his Republican presidential rival was weak on crime and immigration and accusing him of delegating critical decisions during the coronavirus pandemic to Dr. Anthony S. Fauci .
In an appearance with the conservative commentator Ben Shapiro, Mr. DeSantis accused Mr. Trump, the GOP front-runner, of “moving to the left” on criminal justice and immigration issues after winning over the party’s base in 2015 and 2016.
He vowed to repeal what is known as the First Step Act, a bipartisan criminal justice measure signed into law by Mr. Trump in 2018 that expanded early release programs and changed sentencing laws, including mandatory minimum sentences for nonviolent drug offenders.
“He passed a bill, essentially a jailbreak bill,” Mr. DeSantis said. “It has let dangerous people out of prison who have now offended and really, really hurt a number of people.”
This year, The New York Times reported that Mr. DeSantis and his allies viewed the criminal justice bill, which Mr. Trump signed at the urging of his son-in-law Jared Kushner — and promptly regretted — as an area of political weakness, and that Mr. DeSantis had signaled that he wanted to use it in the nomination battle. The bill is unpopular among parts of Trump’s hard core base.
But for Mr. DeSantis, attacking Mr. Trump over the First Step Act is potentially complicated. Mr. DeSantis himself voted for the first version of the bill when he was in Congress, and Trump allies have tried to highlight that fact.
“So now the swamp politician Ron DeSanctimonious claims he voted for it before he voted against it,” Steven Cheung, a spokesman for Mr. Trump, said in a statement. “He sounds exactly like John Kerry. What nonsense! He can’t run away from his disastrous, embarrassing and low-energy campaign announcement. Rookie mistakes and unforced errors – that’s who he is.”
(Mr. DeSantis’ allies note that the version of the bill he voted for looked significantly different, and that the final version passed when he was no longer in the House.)
When Mr. Shapiro asked Mr. DeSantis about Mr. Trump’s recent criticism that crime had risen on his watch in Florida, the former president’s adopted state, Mr. DeSantis bristled, saying that Mr. Trump’s policies had undermined law and order.
Mr. DeSantis stepped up his attacks on his former ally, whom he had avoided directly criticizing for months, less than 48 hours after entering the race in a bumpy Twitter event.
And as Mr. DeSantis appears to veer to the right on issues like crime, some of the campaign’s internal strategy is coming to light.
At a fundraiser in Miami on Thursday, donors peppered Mr. DeSantis’s top campaign staff with questions about his policy positions and how they should be presented to other Republicans, according to a leaked audio recording posted online by the website Florida Politics.
A donor asked a question about the shift to the right, to which a campaign official eventually responded, “We just have to win a primary to be in a general.”
The donors and officials also discussed how to talk to Republicans who support abortion rights. (Mr. DeSantis last month signed a six-week abortion ban in Florida, which contains limited exceptions, while Trump has been hesitant to support a federal ban.)
An employee gave one possible answer.
“Abortion is safe, legal and rare in Florida,” he said, echoing a phrase coined by former President Bill Clinton, a Democrat. “It has not been banned,” he added. “It’s limited.”
In his interview with Mr. Shapiro on Friday, Mr. DeSantis sought to appear steadfast on illegal immigration, saying that Mr. Trump had attacked him for opposing amnesty legislation while he was in Congress.
He also faulted Trump for his administration’s handling of the 2020 coronavirus outbreak, particularly the level of influence wielded by Dr. Fauci, the longtime infectious disease expert and face of the federal government’s pandemic response.
Dr. Fauci, who retired in January, has been a frequent target of Republican attacks over issues such as distance learning, stay-at-home orders and vaccine mandates.
“He reacted by elevating Anthony Fauci and really handing the reins over to Dr. Fauci, and I think that has terrible consequences for the United States,” Mr. DeSantis said. “I was the leader in this country in fighting back against Fauci. We opposed him every step of the way.”
He said Dr. Fauci should have been fired, but Mr. Trump had honored him.
“I think the fact that Donald Trump gave Anthony Fauci a presidential commendation on Trump’s last day in office, it was a gut punch to millions of people around this country who were hurt by Fauci’s shutdowns,” DeSantis said.
A day earlier, in a post by Mr. Trump on his Truth Social platform, the former president slammed DeSantis for Florida’s response to the pandemic. He said that even former New York Governor Andrew M. Cuomo had done a better job of limiting the loss of life to the virus than Mr. DeSantis had.
Mr. DeSantis described Mr. Trump’s claim as “very bizarre” and said it suggested he would double down on his actions if there was another pandemic.