Nearly a month after the tragic Parkland shooting, President Trump has found the perfect GOP scapegoat for America's unparalleled gun violence.

Instead of improving gun control laws or repealing the Dickey Amendment, on March 8, the White House held a meeting on the harmful effects of violent video games.

Kicking off the meeting with a montage of video game violence, Trump asked those in attendance, "This is violent, isn't it?"

"I'm hearing more and more people say the level of violence on video games is really shaping young people's thoughts," he added later.

But hearsay is very different to cold hard data, and there was one thing conspicuously missing from Trump's video game intervention: independent research.

"I was very surprised that there were no researchers that were invited to talk — either criminologists, psychologists, or anybody along those lines," Dr. Patrick Markey, a professor of psychology at Villanova University told Teen Vogue.

Dr. Whitney DeCamp, who studies youth violence in public schools, was equally discouraged by the White House meeting.

"Violent behavior is much better predicted with factors of their home life: whether or not they have a close relationship with their parents, whether they see or hear violence in their home or neighborhood, whether they have been the victim of violence themselves," DeCamp's findings reveal.

For years, most experts have agreed that there is no obvious connection between video games and real-life violence. There is even some research that suggests video games actually reduce violent-crime rates.

"Instead of being out in public, where you're more likely to have an altercation with that person, you're inside your living room playing Grand Theft Auto," explained Markey, who coauthored the study that found decreased real-life violence.

Never mind the lack of conclusive data, Trump and other GOP members have firmly latched on to this unsubstantiated idea.

Those who espouse the evils of video game violence are most likely drawing their conclusions from studies that have found temporary boosts in aggression levels directly after playing violent video games.

In 2015, for instance, the American Psychological Association (APA) confirmed a link between violent video games and increased aggression in players. However, the APA also made it very clear that "insufficient evidence exists about whether the link extends to criminal violence or delinquency."

"Scientists have investigated the use of violent video games for more than two decades but to date, there is very limited research addressing whether violent video games cause people to commit acts of criminal violence," said Mark Appelbaum, the APA's task force chair.

"However, the link between violence in video games and increased aggression in players is one of the most studied and best established in the field."

Three years later, the first-of-its-kind longitudinal study has revealed the exact opposite of the APA's conclusion. A long-term study from the Max Planck Institute and the University Clinic Hamburg-Eppendorf in Germany has found zero link between violent video game play and increased levels of aggression in adults.

"The American Psychological Association recently summarized the previous findings on violent video games as indicating that they pose a risk factor for adverse outcomes, including increased aggression and decreased empathy," said lead researcher Simone Kühn.

"The present findings of this study clearly contradict this conclusion."

Kühn's research divided 77 participants into three groups. One group played the violent video game Grand Theft Auto V every day for two months, another group played the simulation game The Sims 3 for the same amount of time, and the final control group did not play any video games at all for two months.

The research compared each participant's aggression levels, interpersonal abilities, impulsivity, anxiety, mood and executive control levels before and after the trial period.

After what sounds like the greatest two months ever, the researchers found no significant personality changes in any one of the three groups, even when it comes to aggression levels.

In fact, only three of the 208 statistical tests showed any indication of more violent behavior, and even then, the researchers explained that these three tests were most likely a biproduct of coincidence.

But what about the lasting effects of video game play?

Two months after the trial ended, there was still no measurable difference in the participants' aggression levels, or any of the other variables tested for that matter.

"We did not find relevant negative effects in response to violent video game playing," said Kühn.

"The fact that we assessed multiple domains, not finding an effect in any of them, makes the present study the most comprehensive in the field."

The study provides strong evidence that this frequently debated effect of violent video games isn't as "established" as the APA or Trump would have the public believe.

Kühn hopes his study will provide a more realistic scientific perspective on the effects of violent video gaming in real life. In the future, he wants similar studies done using children as participants.

Next time Trump holds a White House meeting on video game violence, it might be a good idea to invite Kühn along.

The research was published in Molecular Psychiatry.

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