The criminal justice system knew Decarlos Brown long before he was accused of fatally stabbing Iryna Zarutska, a Ukrainian refugee, in an unprovoked attack on a Charlotte, North Carolina, train in August.

In July, a judge said Decarlos Brown might not be mentally capable of understanding previous charges against him. His criminal history included three felony convictions, according to a USA TODAY review of court documents.

Police say he attacked Iryna Zarutska inside a light rail car in Charlotte, North Carolina on Aug. 22. Brown faces state and federal charges, but court records do not yet show his plea. USA TODAY has reached out to prosecutors and The Mecklenburg County Public Defender's Office.

Since then, video of the attack has stoked a firestorm of controversy that even attracted the attention of President Donald Trump.

In a video posted to the White House's X account, Trump called the suspect "a deranged monster" and blamed "Democrat-run cities that set loose savage, bloodthirsty criminals to prey on innocent people."

Charlotte Mayor Vi Lyles, a Democrat, pointed blame at the criminal justice system in a post on X, calling the killing a "tragic failure by the courts and magistrates."

As politicians present competing explanations for the killing, many Americans grapple with a simple question: How could this happen?

"I was surprised to see this guy was out," said Matthew William Logan, an associate professor at Texas State University's criminal justice school who specializes in prison research. "If you look back at this guy's past, you think, 'How could we not see something like this coming?'"

What we know about Decarlos Brown's criminal past

Since 2007 Decarlos Brown, now 34, has had at least 14 separate cases in the criminal court system in Mecklenburg County, which includes Charlotte.

When he was 22, Brown was charged in at least four separate cases that included shoplifting, larceny, breaking and entering and felony conspiracy. Court records show he was convicted of all of those charges except conspiracy.

Less than a year later, Brown pulled a gun on a man in the middle of the day at a Charlotte apartment complex and robbed him of his cellphone and $450. Brown pleaded guilty as part of a plea deal and a judge sentenced him to serve between six and eight years in prison.

Prison records show Brown spent six years in prison, followed by a year of probation.

His next court case came in January this year, when court records say Brown was at a hospital and someone called police about him. When they arrived, that's when records say Brown told them someone gave him a "manmade material" that was controlling him.

"Officers advised Brown that the issue was a medical issue and that there was nothing further they could do," a police report says. "Brown became upset with officers' answers and with officers still on scene, called 911 to speak with police."

Officers then arrested him on a charge of misuse of 911.

A judge later released him without bail. In July, a different judge agreed with a defense attorney's request to have Brown mentally evaluated for competency to understand the court proceedings he faced. It's unclear whether Brown was evaluated before Zarutska's killing on the light rail.

The Mecklenburg County Public Defender's Office did not respond to a request for comment about Brown.

'Progressive prosecution' may have impacted Brown's cases

Brown's case appears to be part of a criminal justice system trend toward "progressive prosecution," a topic of intense debate among scholars in the field, said Logan, the Texas State University criminal justice professor.

In cities from Los Angeles to Chicago, prosecutors have declined to pursue charges in a number of cases deemed to be low level but that would previously have carried time behind bars.

"The system has been sort of defanged," Logan said. "The default seems to be more hands off than hands on."

Dismissed charges and lighter sentences have come in response to concerns over mass incarceration and a system that historically has been tougher on people of color. Advocates of a lighter touch argue that an overly punitive system can hinder rehabilitation and reintegration into society. They stress providing increased access to mental health care and other wraparound social services.

"Many thousands of people, disproportionately people of color, are cycled in and out of state jails or prisons every day," the American Civil Liberties Union previously said.

What is Charlotte doing to keep people safe?

Charlotte Mayor Vi Lyles said the city would be stepping up police patrols on the light rail and beginning new safety operations. She also said the criminal justice system’s status quo must change.

"Our police officers arrest people only to have them quickly released, which undermines our ability to protect our community and ensure safety," she wrote on X.

"We need a bipartisan solution to address repeat offenders who do not face consequences for their actions and those who cannot get treatment for their mental illness and are allowed to be on the streets."

Logan said judges need to look closer at the likelihood that someone will reoffend based on their criminal history.

"When somebody has an extensive record, at what point do you say, 'You can't play well with others?'" he said. "We're not dealing with some abstract, theoretical, philosophical question or phenomenon. We're playing with people's lives here."

Amanda Lee Myers is a senior crime reporter for USA TODAY. Follow her on X at @amandaleeusat.

This article originally appeared on USA TODAY: Charlotte train stabbing suspect had a long criminal history

Reporting by Amanda Lee Myers, F.T. Norton and N'dea Yancey-Bragg, USA TODAY / USA TODAY

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