An 80-year-old man living near Chicago's O’Hare airport was left "​​battered" late last month when two intruders knocked on his door and entered his home. 

The elderly man was a legal gun owner and managed to fire off a shot, hitting one intruder and sending the other running for cover.

The incident is one of dozens that have played out in the Windy City in recent years. Legally armed citizens are taking matters into their own hands, thwarting attacks and other crimes.

"It's the reason why you've seen the increase in gun sales," said John Lott, president and founder of the Crime Prevention Research Center. "Because people realize that the police and law enforcement broadly isn't being allowed — the criminal justice system isn't being allowed — to go and do its job.

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Man handgun concealed carry

Since 2020, there have been at least 44 incidents of legal gun owners in the Chicago area have who thwarted an attack or other crime, according to an analysis of local media reports. (iStock)

"And the people know that they ultimately have to be responsible for protecting themselves and their families," Lott told Fox News Digital in a recent phone interview.

Fox News Digital analyzed local media reports going back to 2020 and found that there have been at least 44 incidents in which people with a gun, who had concealed carry permits (CCW) or an FOID, an Illinois identification card used for gun possession and purchase, have thwarted an attack or other crime.

There may have been additional incidents that have not been reported by the media or to local police.

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The dozens of documented incidents include concealed carry holders thwarting a car burglary and a would-be carjacker, a resident with a CCW who intervened when he heard a disturbance coming from his neighbor’s home and found a man wielding a knife, and a CCW holder who disrupted a shooting that left one woman dead and two men injured.

In one incident in 2021, a female CCW holder celebrated having her gun on her when criminals approached her outside a bank after she had withdrawn a fistful of cash.

Chicago police cars with their lights on respond to a suspected carjacking and shooting

Chicago Police vehicles at crime scene.  (FOX32 Chicago WFLD)

"Thank God I had my gun, or I’d probably be dead right now," the woman told CBS Chicago at the time, noting that a suspect "looked surprised" when she pulled out her gun and sent the criminals running.

​​Chicago has been rocked by crime in recent years.

Homicides skyrocketed in the city in 2020, following a drop in violence the three previous years. The Windy City recorded 769 homicides in 2020, up 50% from 2019. In 2021, the city broke a 25-year record when it surpassed 800 homicides, the Chicago Tribune reported. Homicides dipped last year to 695, but the figure still ranks as one of the highest since the 1990s.

Murders across the country also skyrocketed in 2020, as the pandemic’s lockdowns upended day-to-day life and protests and riots raged in response to the killing of George Floyd at the hands of Minneapolis officers. Floyd's killing ushered in renewed calls to defund police.

George Floyd riots

A building goes up in flames during the George Floyd riots. (Getty Images)

What was left in the aftermath were police departments across the country facing an exodus of officers and contending with declining morale amid raging anti-cop sentiment. Various officers reported they had to work grueling hours to fill the voids left by the slew of police who resigned or retired. 

In Chicago, the mayor pledged in 2020 to cut $80 million from her city's police budget. Over the summer last year, officers admitted to pulling back from carrying out the rule of law. They cited among their reasons growing hesitation of interacting with "criminals with guns" due to prosecutors having a tighter grip on approving felony charges against criminals.

With more scrutiny, some said they weighed whether making an arrest was worth their life or becoming a prominent news topic and perceived villain.

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"In the past, I might see a guy with a gun in his waistband, and I’d jump out and chase him," one decorated officer told the Chicago Sun-Times in July. "No way I’d do that now."

Arrests were only made in 12% of crime cases in 2021 in Chicago, which is the lowest rate since 2001, the Sun-Times found last year. The number of investigative stops also fell by more than 50% between 2019 and 2021, and fewer crimes were being reported to the police department by both residents and officers on beats.

Concealed carry class

Damon Thueson shows a holster at a concealed carry permit class put on by USA Firearms Training Dec. 19, 2015, in Provo, Utah. (Getty Images)

In 2020, gun sales had a banner year across the country, with an estimated 23 million firearms sold and more than 21 million gun background checks conducted. The numbers smashed records and notably spiked at the onset of the pandemic in March, before jumping yet again in June of that year as protests and riots spread across the nation in response to the killing of Floyd.

In Illinois, obtaining a concealed carry permit is "difficult," but still "possible," according to crime and gun expert Lott.

He compared Illinois to its neighboring state of Indiana, highlighting that a little over 4% of the adult population has concealed carry permits, while in Indiana, that number sits at about 22%. He said the difference comes down to money. It costs nothing to get a concealed carry permit in Indiana, while it's at least $400 in Illinois.

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Lott said the heavy costs placed on Illinois citizens often prevent those who would most benefit from firearms for self-defense — those most likely to be victims of crimes — from going through the required permitting steps, because they don't have the money.

Chicago Bean sculpture

A person takes a photograph of the Cloud Gate sculpture, known as the Bean, at Millennium Park in Chicago July 24, 2020.  (Olivia Obineme/Bloomberg via Getty Images)

"The sad thing is Illinois makes it so difficult for law-abiding citizens to be able to go and protect themselves," Lott said. "They basically have set it up so that primarily the wealthy, well-to-do were able to go and protect themselves.

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"The problem is, is that the people who are most likely victims of violent crime are poor Blacks who live in high-crime parts of Chicago and other places," Lott added.

"And yet, you make them have to pay over $400 to get the permit, get … the state-required training that they have. We're not even talking about the cost of the gun or anything else. That's a real cost."