'I feel terrified': Inventor of 'Glock switch' technology says he regrets creation

When Jorge Leon invented at the age of 22 a small device that turns Glock pistols into fully automatic weapons, he said he intended it to be used for the good of society, to help the military and police in his native country of Venezuela.

But 26 years after being granted a U.S. patent for his "fire selector system," U.S. law enforcement officials say his creation is flooding the streets of American cities with these outlawed machine guns and many have fallen into the hands of teenage criminals indiscriminately using them to wreak havoc on communities both large and small.

"After seeing and reading about all those deaths, those unnecessary deaths of youngsters, of police officers, of broken families, I don’t feel nice about that, I don’t feel good," Leon, now 59, told ABC News. "I regret filing that patent because ... my technology, which was very well protected at that time, is free for everybody."

Leon said that soon after his U.S. patent expired in 2016, he no longer had legal recourse to stop unscrupulous developers from taking his intricate drawings and detailed explanations of how his invention works and manufacturing them for the black markets as so-called "auto sears" or "Glock switches" and illegally selling them on the internet for as little as $20.

“I felt very bad, sure. I felt very bad because I created my invention always looking for the future to help, to help the military, to help SWAT teams, to help like a tool," said Leon, who now invents surgical equipment.

With the official start of summer here, police across the nation are bracing for what one law enforcement expert described to ABC News as the "next level" of gun violence. Law enforcement officials attribute a dramatic increase in the number of shots fired at crime scenes across the country to a lethal combination: multiple people drawing guns in crowded settings to settle disputes and a growing number of criminals using Glock firearms converted to machine guns with extended magazines.

In numerous shootings that have erupted this year, police said Glock pistols fitted with auto sears devices have dramatically increased the number of people killed or injured.

"What that's telling us is that criminals who already are owning these handguns illegally are now taking it to the next level, and they are trying to maximize the destruction that they cause," Jillian Snider, a former New York City police officer and an adjunct lecturer at John Jay College of Criminal Justice, told ABC News.

In a recent interview with ABC News, Martin Collins Jr. said his 19-year-old son, Marsiah, was one of four people killed in a shooting that erupted at a Sweet 16 birthday party in Dadeville, Alabama, on April 15, 2023, in which, according to police, a Glock with an auto sear device was used. Another 32 people were wounded in the shooting and police collected 89 shell casings at the scene.

"It's the worst invention in American history, in world history," Collins called Leon's device.

In the year since his son was killed, Collins, a Marine who served in Iraq, said he has spoken with local, state, and federal officials, telling them converted guns are not just killing victims, but devastating entire families.

"I tell every congressman, congresswoman, senator, state representative, local representative until you walk into a funeral home and see your 19-year-old son wrapped in plastic from the morgue and knowing what they did to him, you will never understand," Collins said. "But I live with that every day because I went to see what they did to my son."

"They're falling into the wrong hands. They are falling into the hands of teenagers and young adults. Folks are making just horrible decisions, impulsive decisions with the inability to resolve relatively basic conflict," Detroit Police Chief James White told ABC News after four people were wounded, two critically, in a June 1 shooting in which 93 shell casings and eight guns, including a Glock with an auto sear, were recovered at the crime scene.

On March 6, eight teenagers, ages 15 to 17, were shot at a Philadelphia SEPTA bus stop by three masked gunmen who opened fire, spraying more than 30 shots in a matter of seconds, according to the Philadelphia Police Department. One of the guns seized in the crime was a Glock 22 pistol with an auto sear and laser sights. Five suspects, ranging in age from 15 to 19, were arrested and charged in the shooting, according to police.

On April 20, two people were killed and seven were injured at a block party in Memphis, Tennessee, when multiple people pulled out guns, including at least one fitted with a auto sear, and opened fire, according to the Memphis Police Department.

On April 12, 2024, Memphis police officer Joseph McKinney was killed and two other officers were wounded in a firefight that erupted as they responded to a suspicious vehicle call. They were confronted by two teenagers in the car, one armed with a handgun modified with an auto sear, according to the Memphis Police Department. An 18-year-old suspect was killed and a 17-year-old accomplice was wounded, police said.

On April 11, 2024, a 14-year-old boy was arrested in Columbia, South Carolina, and charged with murder in the fatal shooting of a 16-year-old boy and his father during a robbery, according to the Columbia Police Department. Police said the young suspect, who shot himself in the leg during the incident, was armed with a pistol illegally modified with an auto sear.

According to a 2023 report by the federal Bureau of Alcohol, Tobacco, Firearms and Explosives, 5,454 guns with machine-gun conversion devices were taken into ATF custody at crime scenes between 2017 and 2021, a 570% increase in the five-year period.

'It's going to get worse'

Asked about teenagers as young as 14 wielding guns equipped with an auto sear that can now be produced with 3-D printers, Leon responded, "I feel terrified."

He said there are tens of millions of Glock pistols in the United States, most owned by responsible gun owners, but each capable of being converted into machine guns in as little as 15 seconds.

"It's going to get worse. Just imagine the quantity of Glock pistols that are out on the streets," he said of one of the most popular guns sold in the United States.

From slingshots to guns

Leon said he has had a passion for inventing things since he was a child, recalling that at age 12 he built the most powerful slingshot on his block.

"At 15, I designed my own car, and I built it. At the same age, I made a working microscope for biology class," he said. "Guns were something that caught my attention because of the precision required and the complexity of the components in order to function."

Leon said that he was 16 years old and working at a gun repair shop in Venezuela when Glock first introduced its firearms in the county in the mid-1980s. He said that after studying the Glock pistol closely, he discovered it did not have an external manual safety but did come with a trigger safety mechanism that prevents the guns from firing if accidentally dropped or bumped from the side.

He said he became obsessed with inventing an external manual safety for the Glock. But as he set out to build one, he discovered what he described as "a gate left open" by inventor Gaston Glock: Manipulating the gun's trigger bar could convert the weapon from a semiautomatic, which requires a pull of the trigger for each shot fired, into a fully automatic weapon in which numerous rounds can be fired by depressing the trigger and holding it.

“I discover some kind of a design flaw in that particular gun," Leon said.

Leon said that when Gaston Glock, an Austrian engineer, got word of his full-automatic conversion device, he asked to meet him while on a visit to Venezuela in the late 1980s.

"We sat and had breakfast at his hotel for him to see my invention. So that happened. And he suggested to me to leave that as a curiosity," said Leon.

Georgia-based Glock Inc. does not make the auto sears and has no affiliation with those who manufacture them. The company did not respond to requests from ABC News for comment.

Leon said he continued working on his design in private, creating six different prototypes. The last one, he said was "very light, very reliable, with very few moving parts."

He said he did nothing further with his invention until a friend working in the intellectual property field asked him in 1996 if he was interested in getting the device patented in the United States.

"Together, with intellectual property lawyers in New York, I filed that document and I introduced that patent in 1996," Leon said. "Two years later, I got the patent pending certificate."

Leon said he was "surprised" that his patent was approved, given the laws against possessing machine guns in the United States.

In 1934, the National Firearms Act was signed into law by President Franklin Delano Roosevelt, outlawing machine guns that were being used by gangsters against police and rivals, including the 1929 Saint Valentine's Day Massacre in Chicago when famed mob boss Al Capone's crew used machine guns, or Tommy Guns, to kill seven members of a rival gang. The law defined the term machine gun to include "parts designed and intended for use in converting a weapon into a machine gun."

In 1994, five years before Leon's invention was patented, President Bill Clinton signed the Federal Assault Weapons Ban, which outlawed military-style semiautomatic weapons and high-capacity magazines that hold more than 10 bullets. The ban expired in 2004.

“My technology was clearly defined in that patent, every dimension, every detail, the physics, the properties, how it works ... so in this way, there was very explicit information there in the patent. Anyone reading the patent could understand perfectly how it works," Leon said.

Under the rules of the U.S. Patent and Trademark Office, the agency must grant a patent when an application meets the statutory requirements under which a patent may be obtained, including being novel, non-obvious, adequately described and enabled, and falls within one of the classes of subject matter that are eligible for patent protection.

There is no statutory authority for the U.S. Patent and Trade Office to determine whether the invention is beneficial to society and the potential uses of an invention can significantly change as technology continues to develop, according to the agency.

"Ownership of a patent does not grant an individual or entity the right to produce the invention, but rather the right to exclude others from making it, using, offering for sale, selling, or importing into the United States the invention claimed in the patent," according to the agency's website.

“I feel like I tried to do the correct thing to keep my technology in safe hands during all that time. But what happened was all the information that was available for everyone who wanted to print out the patent and to make very light, reverse technology and manufacture an illegal Glock switch," Leon said.

Leon said he offered the device to police departments and the military at what he described as a low price. He estimates he has made little money on the device and ceased manufacturing it several years ago.

'No control'

After his patent expired, Leon said his invention "escaped from my hands."

"That, for me, [was] like a heart-crushing feeling because you care about something, then it's not any more yours. It’s something hard because there was no control on that technology anymore," Leon said.

Leon said he felt "frustrated" and helpless as he saw his invention being co-opted and used by criminals.

"We have to find a way how to control this unleashed bad thing that occurred, joined together with the bad design of a Glock pistol and with the stolen technology of the U.S. patent that belonged to me," he said.

According to a lawsuit filed in March against Glock Inc. by the city of Chicago, the Chicago Police Department recovered more than 1,000 Glock guns that had been modified into automatic weapons between January 2021 and Dec. 31, 2023.

"These terrifying weapons have caused death and destruction throughout Chicago: they have been recovered in connection with homicides, aggravated assaults, batteries, kidnappings, burglaries, home invasions, carjackings, and attempted robberies," according to the lawsuit.

The lawsuit alleges that Glock Inc. has known about the dangerous workaround for decades, and mentions in a footnote Gaston Glock's meeting "with the inventor of the 'Fire Selector System'" in the late 1980s.

"Glock’s willful decision to not take any meaningful action to address this problem in its sales to civilians -- despite its awareness -- is immoral, unethical, oppressive, unscrupulous and unreasonable," the lawsuit states. "This is especially so given that the aspect of Glocks that allows the pistols to be so easily modified can also be easily changed to prevent that modification."

The lawsuit notes that other guns produced by manufacturers like Smith & Wesson or Sig Sauer cannot be easily converted and would "require time-consuming and difficult engineering well beyond the capability of most civilians."

On June 10, Glock Inc. responded to the lawsuit by filing a motion in the U.S. District Court for the Nothern District of Illinois asking that the litigation be dismissed. In its motion, the company argued that the city of Chicago's complaint "asserts claims that are barred by the Protection of Lawful Commerce in Arms Act [PLCAA]."

"The City’s attempt to hold Glock, Inc. liable for the actions of criminal third parties is precisely the kind of action that prompted Congress in 2005 to enact the Protection of Lawful Commerce in Arms Act," according to Glock's motion. "With limited exceptions, the PLCAA bars actions that seek to hold firearm manufacturers like Glock, Inc. liable for alleged injuries 'resulting from the criminal or unlawful misuse' of a firearm by a third party."

In its lawsuit, the city alleged Glock is violating the Illinois Consumer Fraud and Deceptive Business Practices Act (ICFA), but Glock countered that the "ICFA is unconstitutional because it interferes with interstate commerce, is unconstitutionally vague, and violates the Second Amendment."

"Just as Chicago looks to blame certain carmakers for the City’s inability to stop auto thefts in the City, Chicago seeks to place the blame on Glock, Inc. for crime involving the use of Modified Glock Pistols," according to the company's motion. "Chicago does not claim that Glock pistols fail to function properly when they are sold by Glock, Inc. and, in light of their popularity and reliability, does not seek to restrict their sale to, or use by, law enforcement."

Glock's attorneys also stated in its motion, "Like all semi-automatic pistols, Glock pistols can be illegally converted to fire fully automatic through the installation of a device known as an auto sear."

The company added that the city filed a similar lawsuit against Glock and other gun manufacturers 20 years ago "arguing that their sale of legal handguns created a public nuisance in the City based on third parties who illegally possessed them and used them to commit crimes."

"The Illinois Supreme Court unanimously held that the City’s complaint failed to state claims under Illinois law based on lack of duty and proximate cause," according to Glock's motion.

'The American people don't deserve this'

Leon said he sent a letter on May 13 to Glock's general counsel Carlos Guevara about re-designing the mechanical configuration of its guns so they will no longer accept auto sears, but has received no response.

He said he hopes to speak with American lawmakers soon to explain to them the problem and come up with a solution.

“The Glock mechanical configuration should be banned, just the configuration until the company comes up with a newly designed weapon," Leon said.

He added that such a ban has to be national instead of state by state, noting that people could go to neighboring states with no ban to purchase Glock weapons.

"When something wrong happens with a car and provokes an accident or something, they recall all the cars in order to make a correction. But what do we see in the gun industry? Nothing. People die every day and the gun industry is mute," Leon said.

He said he began speaking out earlier this year for the first time after being contacted by a Minnesota television journalist about the rise of the auto sear. Leon said he decided to publicly address the issue after undergoing life-threatening open heart surgery late last year that gave him a new lease on life.

"If I am going to invest my time in something, the time I have left, I want to do it for the right causes. I want to do it for something that will promote life," Leon said. "This is my word of commitment that I am looking forward to helping and cooperating with a solution because the American people don't deserve this. They don't deserve this crime rising because of the full-auto."