The M-134G Minigun is one of the fiercest firearms on the planet. The six-barrel rotary machine gun has, over the years, been capable of firing between 2,000 and 6,000 rounds of ammunition per minute. The US military has historically equipped some of its helicopters, fighter planes, and other vehicles with the miniguns to rain hot lead on enemy positions in combat zones across the world.

As a fully automatic firearm, the minigun is tough to acquire even if you are a law-abiding gun enthusiast with a permit—even in gun-crazy modern America. All machine guns manufactured after 1986 are banned under a Reagan-era law, and a civilian who wants to legally buy one made before that date either has to be a federally licensed firearms dealer or at least go through a rigorous, six-month-long federal background check by the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF).

Yet, between 2014 and 2017, a pair of Texas gun dealers—one of whom used to be a cop himself—and an Arizona-based minigun manufacturer engaged in a racket that illegally sold parts to assemble the guns, along with a massive cache of other assault rifles and ammunition, which were then smuggled into Mexico.

Michael Fox, an ex-cop who became a licensed firearms dealer, admitted in a recent federal court case that he sold multiple .50 caliber rifles, thousands of rounds of ammunition and minigun parts to 28-year-old Tyler Carlson, who then transferred the weapons to an unnamed individual, who in turn smuggled the weapons into Mexico. Fox obtained the parts to the minigun from Tracy Garwood, a 62-year-old firearms manufacturer from Scottsdale, Arizona, who was unaware the components he made were smuggled to Mexico, according to a federal criminal complaint.

In April, the three men were each charged with federal crimes. Garwood, a government contractor, pleaded guilty in May to conspiracy to commit an offense or defraud the US and was sentenced to two years probation in September. Carlson pleaded guilty in April to both conspiracy and possession of an illegal machine gun charges, and last month, was sentenced to nearly six years in prison.

Fox, meanwhile, pleaded guilty to conspiring to violate various federal gun laws in July, and his sentencing was scheduled for January. Lawyers for Garwood, Carlson and Fox all declined comment for this story. But the saga represents what gun-trafficking experts described as a rare, successful ATF probe of a major gun-running operation exposing how the black market for firearms across the southwest US has flourished even as Donald Trump has made a parlor game of demonizing migrants at the border.

Just to make the contrast that much sharper with the Trump vision of the world, in this case, the man at the center of it was a dirty former member of law enforcement. The results of the gun trade and ongoing drug war have been especially deadly in Tamaulipas, the Mexican state close to the Texas border near Austin, where Fox and Carlson operated: The number of murders in Tamaulipas reportedly nearly doubled from 682 in 2015 to 1,204 in 2017 as a result of a war between splintered factions of the Gulf and Zeta cartels.

“These guys were involved in trafficking absolutely lethal weapons into Mexico, which is interesting in the context of how the Trump administration is saying the threat is coming from Mexico,” David Chipman, a senior policy advisor for gun-safety organization Giffords Courage to Fight Gun Violence, told me. “With this case, it looks like America is a bigger threat to Mexico.”

A 25-year veteran of the ATF, Chipman said the agency was severely undermanned and underfunded when it came to effectively combating gun trafficking in the Southwestern border states of Texas, New Mexico and Arizona. What’s more, those states have historically had a collective firearm export rates three times that of California, a state with much tougher gun control laws. Nationally, the Bureau had 2,623 employees and an annual budget of about $1.25 billion last year. “That is smaller than the Chicago Police Department and the latest aircraft carrier built was $13 billion,” Chipman told me. “How many cases are out there that ATF doesn’t know about because it doesn’t have the resources to go after them? We don’t catch them all.”

Sam Rabadi, a law-enforcement intelligence firm business development director who served as special agent in charge of ATF’s Philadelphia field office, said it wasn’t just one agency dropping the ball here amid a wave of right-wing demagoguery. Federal law enforcement manning the border have been required to attempt to prevent both contraband and undocumented immigrants from entering the country, he noted. “We are more focused on what is coming inbound than what is going outbound,” Rabadi said. “And the Southwest is a massive area covering thousands of miles. It’s like putting a finger in a leaky dyke.”

Spokespersons for ATF’s Washington DC headquarters and the Dallas-Fort Worth field office declined comment, but a recent report tracing guns recovered in Mexico showed that the supply of firearms crossing the border has been generous—and steady. Between 2012 and 2017, an average of 69 percent of the 99,654 Mexican-traced guns in the report were either manufactured in the US or imported into the US and then transported to Mexico, the March 2018 document showed. The total number of guns recovered in Mexico and traced by ATF has fluctuated over the years: For instance, 17,799 firearms recovered in Mexico were tracked in 2015. A year later, the number dropped to 13,710 only to shoot up again in 2017 to 15,316. The stats are compiled when Mexican law enforcement agencies turn over firearms recovered at crime scenes to the ATF.

During the same five-year period, ATF was unable to trace the original gun purchaser for roughly 50 percent of the firearms that came from the United States and ended up in Mexico.

Chipman said ATF investigations typically resulted from tips provided by informants and scrupulous gun dealers against people buying guns at a generous clip and suspect volume. “I often thought ATF stood for ‘After the Fact” because we are very good at solving crimes that already happened,” he said. “In a perfect world, you would have a mechanism to stop gun trafficking from happening. ATF has tried a number of different strategies to prevent it, but we’ve been hampered by America’s own gun laws that make it easy for anyone to get a firearm.”

Rabadi said the biggest problem was that there hasn’t been any real tracking system in place to cover once a gun leaves a gun store, making it easy for shady dealers to use straw buyers to make purchases. Furthermore, due to Mexico’s ban on assault weapons, there is a voracious demand for semiautomatic and automatic rifles from the country’s criminal organizations, he noted. “As a special agent, you are trying to discern between someone who is buying one for protection or sport with someone who is trying to make money by re-selling guns illegally,” he said. “It takes time to build these investigations.”

According to court documents in the minigun case, Carlson approached Fox in the summer of 2015 with parts from a minigun and asked him if he could build it into a functioning weapon. Fox agreed, but at the time did not know the minigun would be smuggled to Mexico. He subsequently found out and continued to supply Carlson with firearms.

Fox obtained minigun components made by Garwood—parts the gun manufacturer had reported as destroyed to the feds. Special agents recovered some of those parts during a February 2017 raid of Fox’s house in Georgetown, Texas, according to the criminal complaint. During the investigation, federal agents twice intercepted shipments of firearms bound for Mexico that they traced back to Carlson and Fox. On June 3, 2016, near McAllen, Texas, minigun parts, 15 AK-47 rifles, four handguns, and 4,000 rounds of assorted ammunition were seized, and six months later, another seizure turned up roughly 30 guns, smoke grenades, and thousands of rounds of ammunition near Weslaco, Texas.

The complaint suggests Fox successfully built multiple miniguns he unlawfully transferred to Carlson that were successfully smuggled into Mexico. According to Carlson’s sentencing memorandum, some of the weapons may have landed in the hands of an unnamed drug cartel.

John Lindsay-Poland, a gun-control advocate who serves as coordinator for the Stop US Arms to Mexico project, told me the type of gun trafficking committed by Carlson and Fox has far-reaching impact beyond North America. Which only made the ongoing race-baiting of alleged criminals at the border—which flared up again when the president argued with Nancy Pelosi and Chuck Schumer about it in front of the press Tuesday—all the more glaring.

“For people fleeing Central America and passing through Mexico, they are being afflicted by greater gun violence than any other time in their history,” Lindsay-Poland told me. “They are fleeing to the US in large part because criminals in their countries are using guns coming from the US, making life unsustainable in places like Honduras and Guatemala. And they are traveling routes controlled by organized crime that receive their guns from the illegal gun trade in the US.”

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