(WASHINGTON) — Republican presidential candidate Chris Christie said Sunday that rival Donald Trump should not shrug off his mounting indictments, all of which he denies.

“Trump needs to be smart and careful about this, if that’s at all possible. Which is that he is a criminal defendant,” Christie told ABC “This Week” co-anchor Jonathan Karl.

Christie, a former governor of New Jersey, former ABC News contributor and former Trump ally-turned-critic, stressed that Trump being prosecuted in three different criminal cases, with a fourth potentially coming in Georgia, means both he and Republican voters will have to navigate uncharted waters.

Trump has pleaded not guilty to all of his charges, which so far come out of New York state court, federal court in Florida and federal court in Washington, D.C. An Atlanta-area prosecutor is expected this week to present a fourth case to a grand jury there.

Some restrictions have been placed on Trump related to his indictments, such as a protective order issued by the federal judge overseeing his Jan. 6 case in Washington. That order bars the disclosure of “sensitive” information that Trump will learn via discovery from prosecutors. The judge also warned against “inflammatory statements” that “could taint the jury pool or intimidate potential witnesses.”

The judge in Trump’s New York state case issued a similar order.

Christie said on “This Week” that “you get subject to certain restrictions, and the reason you’re subject to those restrictions is because a grand jury has found there’s probable cause that you’ve committed criminal acts.”

Challenging the view of the federal judge in Washington — who said “the existence of a political campaign will not have any bearing on my decision” — Christie said that “I think it is impossible to not have politics inform some of this case. It’s not a normal criminal case, and so politics is going to inform some of it.”

Trump is slated to go on trial next year at the same time that he will also be on the campaign trial in the thick of the Republican primary — meaning GOP voters can render their own judgment, Christie said.

“I think all of these things are things people are going to have to process for the very first time in a presidential race,” he said. “And what I think Republican voters have to ask themselves is two things: First is, is he really the guy under indictment in four different cases, given the conduct that he committed, someone who can beat Joe Biden or any other Democrat in November 2024? And when are we going to stop pretending that this is normal?”

Christie previously ran for president in 2016 and launched a second presidential bid in early June. He hasn’t hesitated to denounce the former president, including at nearly every one of his campaign events thus far.

Trump, for his part, has dismissed Christie as a “failed” candidate and governor and early polls so far show Christie badly trailing Trump and other hopefuls.

On “This Week,” Karl cited a widely circulated video from a debate during the 2016 campaign when Christie hammered opponent Marco Rubio.

“Looking back at all that has happened since then, do you ever wish that you had taken that swing at Donald Trump and not at Marco Rubio?” Karl asked.

Christie responded, “I wish I’d taken swings of both of them, Jon, looking back on it.”

“We all made a mistake in 2016: Myself, Marco, Jeb Bush, John Kasich, in not going after Donald Trump,” Christie continued, referring to other 2016 Republican candidates — each of whom at different times were seen as more legitimate than Trump, the eventual winner.

“I think we were under the illusion that somehow what was obvious to us at the moment, that there were some better candidates on stage than him, would be obvious to the public,” Christie said. “It wasn’t. And I think it should inform everybody’s approach to the race this time. Certainly, it’s informing mine.”

The first 2024 Republican primary debate will be held on Aug. 23, in Milwaukee. To make it on the stage, candidates have to sign a loyalty pledge with the Republican National Committee that promises to eventually back whomever wins the nomination.

Both Christie and Trump have criticized the loyalty pledge. Trump said last week that he wouldn’t sign it: “I can name three or four people that I wouldn’t support for president. So right there, there’s a problem.”

He has also suggested he sees no point in attending the first debate, given his polling lead.

“I think that they [the RNC] are serious about wanting this pledge signed, and I do think they would keep Donald Trump off the stage if he chose not to sign the pledge,” Christie said on “This Week.”

Still, “I think this is all kind of nonsensical theater,” he said. “I’ve made that clear to the RNC as well, way back, even before I entered the race, that I thought the pledge was a bad idea, and Donald Trump is now playing that game. But that’s what he does.”

Christie himself has yet to sign the pledge and said Sunday that debate organizers haven’t presented it to him as they are still verifying eligibility for candidates to take the stage.

He has said he will reluctantly sign it and on “This Week” predicted that Trump, despite his protestations, might as well.

“I would not be the least bit surprised if sometime around Sunday or Monday of next week that he signs the pledge, and he shows up on the stage on Wednesday,” Christie said. “He might not also, but I would not be the least bit surprised if he did. This is about Donald Trump keeping the attention on Donald Trump.”

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