A new study published in the Journal of Economic Behavior and Organization has added to an ever-growing body of research which suggests that cannabis legalization is linked to a decrease in violent crime. The study, conducted by researchers at the University of Bologna in Italy, looks at legalization’s effects on crime in the state of Washington.

The findings are the result of a comparison between Washington state, after it legalized in 2012, and the neighboring state of Oregon, which legalized two years later in 2014. That two-year gap allowed researchers to compare violent crime rates across several counties in both states and measure the effects of legalization.

Researchers examined 11 counties in Washington and 10 in Oregon and examined a range of data on crime and substance use. Their findings revealed that the legalization of recreational marijuana was linked to a 15 to 30 percent decrease in reported rapes and a 10 to 20 percent decrease in thefts.

The researchers cite four reasons they believe the legalization of cannabis may have had a positive effect on violent crime rates starting with the suggestion that legalization itself, “reduces the likelihood of [cannabis users and growers] engaging in violent activities.” They go on to say that legalization reduces the likelihood that those growing and selling cannabis will be involved in gang activity while the regulation of a legal market frees up police resources to combat other crimes.

The study also found that residents in legal states reduced their normal and binge alcohol consumption significantly when provided with the alternative of legal weed. Researchers see this reduction in the use of more “violence-inducing substances” like alcohol and cocaine as a contributing factor.

The findings are yet another example of science fighting back against statements made by Attorney General Jeff Sessions. Since being appointed as the country’s top law enforcement official Sessions has linked cannabis to violent crime with seemingly little evidence saying, “I believe it’s an unhealthy practice, and current levels of THC in marijuana are very high compared to what they were a few years ago, and we’re seeing real violence around that.”

After meeting with the Attorney General of Nebraska, Doug Peterson, last year, Sessions directly associated legal marijuana states to an increase in violent crime. He cited Peterson’s concerns that legalization in Colorado has increased crime in neighboring Nebraska.

In 2014, Nebraska brought a case before the Supreme Court claiming damages brought by the state of Colorado as a result of cannabis legalization. The case was dismissed, and Sessions’ claims were debunked by fact-checking website Snopes which found that there was very little evidence to show that legalization was a direct cause of increases in violent crime, both in Colorado and its neighboring states.

Instead, prior research shows that cannabis legalization results in decreased crime rates, supporting the most recent study. Among those previous studies, when researchers examined crime rates across 11 western states in 2016, they found that medical marijuana legalization has “no negative spillover effects” and resulted in significant decreases in violent crime.