Retired detective Kevin Gannon insists the drowning deaths of dozens of college-aged men across America since the late '90s are the work of a serial killer gang, not mere accidents.

The theory of the 20-year veteran of the New York City Police department and his longtime partner, Anthony Duarte, is at the center of an Oxygen docuseries titled “Smiley Face Killers: The Hunt for Justice.”

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The drowned men that Gannon and Duarte call "victims" were all young, athletic and academic achievers. They were all reportedly found dead after a night out drinking. They started appearing in clusters across the country starting 1997. A graffiti of a smiley face was reportedly found near the bodies, and nine of them were drawn with horns, The Telegraph previously reported.

The publication added the claim particularly caused alarm in the neighboring states of Minnesota and Wisconsin, where 19 of the deaths occurred.

Kevin Gannon (right) is participating in a new Oxygen docuseries about his Smiley Face Killers theory. (Anton Floquet)

“Back in 2003 I saw there was like 30 or 40 new cases across the country,” claimed Gannon. “I said, ‘Wow, there can’t be that many cases.’ I started really looking at it and I got my partner Anthony. At that point, we started traveling around the country and looking at these cases independently."

The Oxygen special focuses on the drowning of Dakota James, whose body was recovered from the Ohio River on March 6, 2017, nearly six weeks after he went out drinking with co-workers. The last known sighting of the Duquesne University graduate student was caught on a surveillance camera. The footage captured James entering a dark alley.

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The Pittsburgh Post-Gazette reported the 23-year-old had drowned and his death was ruled an accident by the Allegheny County Medical Examiner’s office, which was a determination strongly disputed by his parents.

Three years earlier, the Pittsburgh Post-Gazette also reported, another Duquesne graduate, 22-year-old Paul Kochu, had vanished after a night out drinking with friends and found dead months later floating 85 miles downriver in Wheeling, W.Va. The West Virginia Medical Examiner ruled Kochu’s death as undetermined.

(Image courtesy of 44 Blue Productions/Oxygen Media)

The Gazette noted that in December 2018, Gannon and forensic pathologist Cyril H. Wecht held a press conference to report that an independent examination on James’ autopsy photos indicated he may have been strangled. Gannon and Wecht said they discovered the appearance of ligature marks, which were inconsistent with a drowning death.

Gannon claimed James’ death was no accident. In fact, he told Oxygen he and Duarte believe there’s a “well-structured, organized gang with cells in major cities across the United States who drug, abduct, hold the victims for a period of time before they murder them and then place them in the water.”

“We look at these young men as being the best of the best as far as we’re concerned,” said Gannon. “They’re the best athletes, and all of them are affluent. They come from the best families. Anthony said years ago that [these killers] could have been envious, jealous of these kids. They had something they didn’t have. That’s a possibility. But also, if you know anything about domestic terrorism, about these gangs in general, is that when you have nothing you have nothing to lose. That’s where terrorism actually begins.”

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The documentary also revealed a smiley face was found spray-painted on an underpass near where James’ body was discovered.

Gannon also pointed out that when James was found by police, his body experienced minimal deterioration, despite being missing for 40 days. Still, the Pittsburgh police theorized James fell into the river while crossing a bridge near the city center and drowned. It is believed James’ body traveled for almost 10 miles and even went through a dam before its discovery.

But not everyone agrees with Gannon’s theory. Over the years, it has been slammed by experts due to reported lack of evidence. Some say it’s nothing more than folklore.

“Over the past several years, law enforcement and the FBI have received information about young, college-aged men who were found deceased in rivers in the Midwest,” said the FBI in a 2008 press release. “The FBI has reviewed the information about the victims provided by two retired police detectives, who have dubbed these incidents the ‘Smiley Face Murders,’ and interviewed an individual who provided information to the detectives.

“To date, we have not developed any evidence to support links between these tragic deaths or any evidence substantiating the theory that these deaths are the work of a serial killer or killers. The vast majority of these instances appear to be alcohol-related drownings. The FBI will continue to work with the local police in the affected areas to provide support as requested.”

(Anton Floquet)

In 2010, the Center for Homicide Research also published a lengthy report debunking the Smiley Face Killers theory.

Gannon said he isn’t fazed by the criticism. In fact, The Daily Beast reported he has mortgaged his home and maxed out his credit cards trying to solve these cases. The publication added that the only thing that stopped him for 18 months was a bout with cancer in 2004.

“I know there was some homicide group that said we didn’t know what we were talking about, but I never saw one piece of forensic evidence in that group to disprove us,” said Gannon. “All they did was take articles from the news media and linked them together as a paper. Any kid in high school could write that paper. That’s not a comprehensive paper.”

“People have their own opinions,” he added. “That was one of the reasons we wrote a forensic textbook to provide homicides. … if we were wrong about these cases being homicides, we wanted to know for sure. Nobody ever came to us to show us that they missed this critical piece of evidence in these cases that were homicides.”

(Anton Floquet)

The Daily Beast added that some change did come from questioning these cases. Chris Jenkins, a 21-year-old University of Minnesota student, vanished after leaving a Minneapolis bar in 2002. His body was found floating in the Mississippi River on his back with his arms crossed across his chest four months later. The site noted that while Jenkins’ death was initially classified as an accidental drowning, police later agreed to change it to homicide in 2006.

James' parents participated in the Oxygen show to set the record straight about their son. They previously launched a nonprofit organization to help other families in similar situations.

“He worked full-time, lived on his own, and was attending college full-time to earn his master’s degree in a city he loved,” they wrote. “He was very active in swimming, running, biking and loved music and dancing. He enjoyed life to the fullest and trusted everyone. His future plans included attending law school, traveling, getting married and starting a family.

“… We struggled on a daily basis trying to find answers-running into red tape and contradicting policies of local agencies and unresponsive authority figures. We did not know where to turn for help. We want to make changes so that this doesn’t happen to the next family of a missing person.”

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Gannon added the Oxygen show will allow viewers to see and judge for themselves. But his goal is to help find answers for grieving family members still wondering what led to such a tragic demise.

“We thought, you know what, let’s put out what we have in the court of public opinion,” he said. “And if the people don’t think there is anything here, then you know, that’s it. But… a lot of experts are going to come up on this show. … And we want them to look at [these cases].”

"Smiley Face Killers: The Hunt for Justice" airs Jan. 19 at 7 p.m. on Oxygen.