A white couple who pointed guns at protesters marching against racial injustice outside their mansion will face criminal charges, the city’s top prosecutor announced on Monday. Mark and Patricia McCloskey, both personal injury attorneys in their 60s, will be charged with felony unlawful use of a weapon and a misdemeanor charge of fourth-degree assault. “It is illegal to wave weapons in a threatening manner – that is unlawful in the city of St Louis,” the circuit attorney Kim Gardner told the Associated Press on Monday, arguing that the couples’ actions risked creating a violent situation during an otherwise non-violent protest. “We must protect the right to peacefully protest, and any attempt to chill it through intimidation will not be tolerated,” Gardner said in a statement. While the prosecutor who announced the charges against the McCloskeys said she was “open to recommending” that the McCloskeys participate in a diversion program designed “to reduce unnecessary involvement with the courts”, the case is likely to fuel continued partisan debate over gun rights and racial violence. Supporters of the McCloskeys said they were legally defending their $1.15m home. An attorney for the couple, Joel Schwartz, in a statement called the decision to charge “disheartening as I unequivocally believe no crime was committed”. St Louis, like many cities across the country, has seen demonstrations in the weeks since George Floyd’s death in Minneapolis. The incident in question took place on 28 June, when several hundred people were marching to the home of the Democratic mayor, Lyda Krewson, a few blocks from the McCloskeys’ home. The McCloskeys live on a private street called Portland Place. A police report said the couple heard a loud commotion and saw a large group of people break an iron gate marked with “No Trespassing” and “Private Street” signs. A protest leader, the Rev Darryl Gray, said the gate was open and that protesters didn’t damage it. Video on social media showed the armed couple standing outside their home in the Central West End neighborhood, shouting at protesters. People in the march moved the crowd forward, urging participants to ignore them. According to a statement, Mark McCloskey confronted protesters with a semi-automatic rifle, screamed at them and pointed the weapon at them. The statement said Patricia McCloskey then emerged with a semi-automatic handgun, yelling at protesters to “go” and pointing the gun at them. Protesters feared “being injured due to Patricia McCloskey’s finger being on the trigger, coupled with her excited demeanor”, the statement said. Photographs and the video of the incident immediately went viral, and the St Louis police department initially said that they were investigating the incident, but that it viewed the McCloskeys as the victims, not the perpetrators, of an incident of “trespassing” and “intimidation”. The city’s top prosecutor, who is black, made a different announcement, saying she was “alarmed” to see an incident “where peaceful protestors were met by guns and a violent assault”, and that her office was also investigating. “Make no mistake: we will not tolerate the use of force against those exercising their first amendment rights,” Gardner wrote. Gardner, the first African American circuit attorney in St Louis’ history, was elected in 2016 as one of the country’s new wave of progressive prosecutors, who aimed to reduce mass incarceration and address the stark racial disparities within America’s criminal justice system. Gardner has already spent years battling with the city’s police union and Missouri’s Republican political establishment. Since she announced her investigation into the McCloskeys, powerful white Republicans, including Donald Trump, Missouri’s governor, and the Republican senator Josh Hawley, have rallied behind the wealthy white couple and made clear that they would oppose any attempt to charge them. Trump said in an interview that the idea that the McCloskeys might be prosecuted was “a disgrace”. Republican governor Mike Parson said in a radio interview on Friday that he would probably pardon them if they were to be convicted of anything. Hawley asked the justice department to consider a civil rights investigation of Gardner, suggesting that her investigation of whether the couple violated any laws was an infringement of their constitutional rights and an “an unacceptable abuse of power and threat to the Second Amendment”. Gardner said she has received death threats in the wake of the comments about her by Republican lawmakers, and compared the attacks against her to violent threats by the Ku Klux Klan in an interview with the Washington Post last week. “This is a modern-day night ride, and everybody knows it,” Gardner told the Washington Post, referring to the Ku Klux Klan’s tactics of intimidation towards Black Americans. “And for a president to participate in it, in the larger context of racism and cronyism, is scary.” Several Black leaders in St Louis have expressed support for Gardner, including the Democratic US representative William Lacy Clay, who has said protesters “should never be subject to the threat of deadly force, whether by individuals or by the police”. In January, Gardner filed a federal lawsuit accusing the city, the police union and others of a coordinated and racist conspiracy aimed at forcing her out of office. The lawsuit also accused “entrenched interests” of intentionally impeding her efforts to change racist practices. Agencies contributed reporting