When a young woman was sexually assaulted and nearly kidnapped while waiting for a bus in Minneapolis’ Near North neighborhood late last month, her attacker vanished before police could arrive. In no time at all, a platoon of armchair criminologists and consulting detectives was on the case.

On one oft-visited Facebook page that reports on local lawlessness, some questioned the wisdom of hanging out in a neighborhood known for blighted conditions and crime. That line of reasoning didn’t sit well with everyone, though.

“It’s disgusting that the blame here is being placed on a woman trying to take the bus and mind her own business,” one commenter countered. “Why not urge people to not perpetuate sexual assault?”

Others argued that the area’s problems stem from a few bad apples, while calling for more police protection in the area.

In some ways, the freewheeling debate that followed was a microcosm of the complicated feelings toward crime nationally. The rise of social media sites like Facebook, Twitter and Instagram — and others that grant their users anonymity — have created a permanent record of the sort of back-fence gossip that never used to go beyond that block, much less the neighborhood.

Rana May, who moderates a Facebook group for northeast Minneapolis residents called “Northeast Vent,” said that many online users seem either unaware or uncaring of changing community standards. Victim-blaming is a common occurrence on some sites, she said.

“There’s a lot of crime posts where they talk about the victims of a crime before their families know they’re the victims of a crime, or they talk about an accident, and I don’t think that’s necessarily healthy,” said May. “A lot of times they devolve into name-calling,” she said, which can escalate into a physical altercation.

May is also part of a private Facebook page for local female comedians to share their own encounters with sexual abuse and harassment in the entertainment industry. There, she says, commenters strike a more empathetic tone.

“They know that no one besides our peers are going to see what they write, but they’re still respectful in the way they use their language and the way they talk about incidents, and so it’s bizarre there’s a difference between that and a giant public group,” said May, who uses a pseudonym because of the nature of her work with a north Minneapolis nonprofit that provides services to teenage parents grappling with homelessness.

The language that people use to talk about crime is laden with meaning, experts say.

In one 2015 study, people who saw crime as a “virus” afflicting society tended to be in favor of addressing the social forces — such as poverty, inequality and poor housing — that spawn criminal activity, while those who thought of it as a “beast” generally pressed for more aggressive policing.

Criminologists say that many people fall victim to fallacies about criminals’ age and ingenuity, which seems to hinge largely on news media and popular culture portrayals.

Joachim Savelsberg, a sociology professor at the University of Minnesota, says it’s difficult to tell whether public opinion about crime is shaped by political attitudes or the other way around.

“If you go back to the very old days of [President Dwight D.] Eisenhower, when he talked about crime in the State of the Union [address], he talked about it in the context of urban problems,” Savelsberg said. “The goal was to destroy the conditions which breed crime and delinquency.”

Years later, he said, Ronald Reagan touted his get-tough-on-crime credentials during a nationally televised presidential address, arguing that “there can be no economic revival in ghettos when the most violent among us are allowed to roam free.”

“If you look at this quote closely, you see it almost entirely turns the logic of Eisenhower upside down,” Savelsberg said.

He said that politicians’ stubborn focus on crime in recent years reflects the fact that Americans’ perceptions of crime rarely square with reality.

This, he says, has contributed to a “vicious cycle between public opinion and political rhetoric.”

As an example, Savelsberg cited President Donald Trump’s repeated warnings of a crime wave sweeping the country. Experts argue that such claims aren’t supported by current statistics, which show crime rates hovering near historic lows.

A 2016 Pew Research Center survey found that more than half of U.S. voters thought that the country has gotten more dangerous since 2008, even as crime rates across the country have cooled, with a few exceptions.