It has been nearly two decades since Canadian snowboarder Ross Rebagliati became the sport’s first Olympic gold medal winner at the 1998 Winter Games in Japan, only to have his title nearly ripped from him entirely due to positive test for marijuana. A few years later, Michael Phelps would become the poster child for the sporting stoner after the swimmer admitted that a photo of him smoking marijuana at a party was legitimate—an incident that caused him to lose at least one major endorsement.

But now that marijuana is legal in over half the United States for medicinal and recreational purposes, not to mention decriminalized in 21 states and handful of nations across the globe, what is the Olympic policy on marijuana as athletes all over the world gather in Rio this week for the 2016 Summer Games?

Fortunately, the attitude toward the use of marijuana in the Olympic scene has progressed a bit over the past few years. Although cannabis remains on the banned substances list, a 2013 policy change by the World Anti-Doping Agency (WADA) raised the limit of marijuana allowed in an athlete’s system to 150 nanograms of THC per milliliter of blood. This means as long as an Olympian does not show up in Brazil stoned, or get high during the games, Olympic officials do not give two, flying squirts about marijuana.

In 2013, Ben Nichols, a spokesperson for WADA, told USA Today that the updated policy on cannabis consumption was only intended to disqualify those athletes who smoke right before or during competition. The rules do not prohibit any of the athletes from using cannabis products outside the event.

“Our information suggests that many cases do not involve game or event-day consumption,” Nichols said. “The new threshold level is an attempt to ensure that in-competition use is detected and not use during the days and weeks before competition.”

Prior to this policy change, four athletes tested positive for THC right before the 2012 Olympic games in London when the U.S. Anti-Doping Agency (USOC) popped its candidates with a drug test. Although this was a very small percentage of the thousands the agency was responsible for testing, the previous threshold for THC did end up disqualifying one athlete—a wrestler by the name of Stephany Lee—and eventually led to another competitor being sent home.

A year after Lee’s dismissal from the games, USOC chief communications officer Patrick Sandusky told USA Today that, “we respect WADA’s decision-making expertise and processes—they decide what is banned and what thresholds to apply and we work to ensure that U.S. athletes are appropriately educated.”

Interestingly, marijuana has only been on the banned substances list since around 1999. In fact, although Olympic officials did initially strip the gold medal from snowboarder Ross Rebagliati back in 1998 for testing positive for marijuana, they eventually had to give it back because they found that pot was not actually a banned substances. Of course, the formation of the World Anti-Doping Agency soon put a stop to that.

But why do Olympic officials even care about marijuana?

In a 2014 interview with Aljazeera America, Dr. Richard Budgett, medical director for the International Olympic Committee (IOC) cited three criteria for a drug to be included on the banned substances list: performance enhancement qualities, health risk factors and whether it goes against the spirit of the sport. In regard to marijuana, Budgett said it “is at least two of those: harmful to health and against the spirit of the sport.”

However, the updated policy on marijuana is the result of a heated negotiation between those members of the committee who do not consider marijuana to be a performance enhancement drug and those, like IOC medical commission chairman Arne Ljungqvist, who believes, “yes, marijuana can be a performance-enhancing stimulant.”

Basically, the Olympics now handle marijuana similar to how it does alcohol. The prohibited substances list indicates that alcohol is banned “In-Competition only” in various sports, so even though marijuana detection times may last up to 90 days, it might not disqualify an Olympic athlete.