Florida police have charged Donald Trump's campaign manager with simple battery in an incident earlier in the month involving a reporter. Trump decried the charges.

Police in Jupiter, Florida, issued Corey Lewandowski a notice Tuesday to appear before a judge on May 4 for the misdemeanor charge. A surveillance video released by the police appears to show Lewandowski grabbing then-Breitbart News reporter Michelle Fields as she tried to ask Trump a question during a March 8 campaign event.

Trump defended Lewandowski Tuesday afternoon, telling reporters he doesn't "discard people" and calling the situation "very unfair" to his adviser. Speaking to reporters on his plane shortly after landing in Wisconsin for a rally, he said he hopes the matter doesn't change Lewandowski's role on his campaign.

"I can't just stand by and watch a man's life be destroyed," Trump said. "I'm sticking up for a person because I'm not going to let a person's life be destroyed. No jury, in my opinion, would convict a man and destroy a man's life over what you witnessed."

The Trump campaign had earlier said Lewandowski "is absolutely innocent of this charge" in a statement released late Tuesday morning.

"He will enter a plea of not guilty and looks forward to his day in court," read the statement. "He is completely confident that he will be exonerated."

Lewandowski has retained a Florida attorney who said Tuesday there would be no further comment.

The charge, a first-degree misdemeanor, carries a potential sentence of up to 1 year in prison or up to a $1,000 fine, according to Florida statutes.

The news that Lewandowski was being charged also prompted a Twitter exchange with Fields.

"Why aren't people looking at this reporters earliest statement as to what happened, that is before she found out the episode was on tape?" Trump tweeted.

Fields responded: "Because my story never changed. Seriously, just stop lying."

Trump's rivals seized on the news, which comes a week before a high-profile contest in Wisconsin and in the midst of a messy Republican primary season.

Texas Sen. Ted Cruz said the incident is "the consequence of the culture of the Trump campaign — the abusive culture when you have a campaign that is built on personal insults, on attacks and now physical violence."

"That has no place in a political campaign, it has no place in our democracy," Cruz told reporters as he campaigned in Wisconsin, suggesting that "it helps clarify for the voters what the trump campaign is all about."

Cruz's top aide, Rick Tyler, resigned in February for spreading a story that falsely alleged former rival Marco Rubio insulted the Bible.

"If he worked for John Kasich he would be fired," said John Weaver, a senior adviser to Ohio Gov. John Kasich. "Campaigns though always reflect the values of the candidate. I know ours does."

At the time of the incident, Lewandowski tweeted, "@MichelleFields you are totally delusional. I never touched you. As a matter of fact, I have never even met you." Trump accused her of having "made up" the incident.

A police report obtained by The Associated Press includes an interview with the reporter, Fields, who worked for Breitbart News at the time.

"Lewandowski grabbed Fields' left arm with his right hand causing her to turn and step back," reads the report. Fields showed police her left forearm which "appeared to show a grabbing-type injury," according to the investigating officer.

At his rally in Wisconsin, Trump discussed what remembered from the incident, including that he flinched in reaction to Fields arriving in a press scrum surrounding him. He also repeated his claim that Fields changed her story from the immediate aftermath of the incident.

"I'm not going to destroy a man for that," he said. "At first I saw that and I said, this is terrible. Then I saw it on tape."

Fields resigned from the the conservative news site over its response to the alleged assault. Three of her colleagues also resigned.

The site initially issued a statement backing Fields and calling on Lewandowski to apologized. Later, it published images questioning whether the Washington Post's Ben Terris misidentified Lewandowski as the person who may have physically assaulted Fields. Breitbart later published a piece purporting to show text messages from Lewandowski which it said "prove" he didn't assault Fields.

Fields said in a statement issued to Buzzfeed on March 14: "I do not believe Breitbart News has adequately stood by me during the events of the past week and because of that I believe it is now best for us to part ways."