Steve Fox, a co-author of “Marijuana Is Safer: So Why Are We Driving People to Drink?,” is of counsel at Vicente Sederberg, a marijuana-industry law firm in Denver.

It’s been a big year for NFL fans in Denver and Seattle. On the field, the Broncos and the Seahawks had dominant regular seasons and cruised into the playoffs. Off the field, ballot initiatives that passed in 2012 went into effect, making it legal for adults in Colorado and Washington to possess and consume marijuana. So fans in those states now have the option of grabbing a Bud Light (proud sponsor of the NFL) or lighting a bud while watching a game at home.

NFL players, however, do not enjoy the same freedom. Instead, they are subject to drug testing — not just for performance-enhancing substances but for “substances of abuse,” including marijuana. Those screenings tend to be sporadic but can become far more frequent after an initial positive test. Testing positive just once can get a player suspended, without pay, for four games. By comparison, the National Hockey League tests only for performance-enhancing drugs. And while Major League Baseball and the National Basketball Association do test for marijuana, their penalties are much less harsh.

The Broncos and the Seahawks have each lost key players this season to marijuana-related suspensions. Denver’s Von Miller, the 2011 NFL defensive rookie of the year, missed the first six games for allegedly failing drug tests and failing to comply with league drug testing . (Miller is now out for the season with a knee injury.) And the Seahawks lost starting cornerback Walter Thurmond for four games during the latter part of the season, reportedly for testing positive for marijuana. Less than a month later, the league suspended Seahawks cornerback Brandon Browner indefinitely for failing a drug test. Again, it was believed that marijuana was the culprit.

These are just a few of the many marijuana-related suspensions handed down by the NFL over the past decade. Most famously, Heisman Trophy-winning running back Ricky Williams retired from the league in 2004 when faced with a suspension for repeated marijuana use. Just two seasons earlier, he led the NFL in rushing, and in the 2002 and 2003 seasons combined, he gained more than 3,000 yards. Williams returned to the NFL in 2005, served a full-year suspension after another violation in 2006 and finally retired from football in 2012.

(Alex Nabaum for The Washington Post)

Such suspensions unfairly deny the league and its fans of talented players who are not hurting anyone and are not cheating: Marijuana is not a performance-enhancing drug. There is no reason to punish players for using it in their free time.

What makes these suspensions all the more unjust is that marijuana use seems to be pretty common in the NFL. Lomas Brown, a former Detroit Lion and longtime ESPN analyst, estimated in 2012 that at least 50 percent of players use marijuana, a share he said was down from about 90 percent when he entered the league in 1985. Former Seahawk John Moffitt recently echoed Brown’s estimate of at least half, adding: “If you’re an athlete and you’re drinking [alcohol], you’re deteriorating your body far more than if you’re an athlete and you’re using marijuana.”

Sure, unlike alcohol, marijuana is illegal, at least federally. And those opposing it may think that if someone is dumb enough to use an illegal drug, in violation of his employer’s policy, he deserves whatever punishment he gets.

But consider a far more serious issue: chronic pain. While some players might use marijuana simply to unwind — just as other players might have a beer or two — many of them also use it for the pain they are subjected to as warriors in a brutal game.

Former Broncos tight end Nate Jackson recently discussed this with the Denver Post: NFL players “live in a great deal of pain on a daily basis, and marijuana helps with that. . . . Teams pass out opioid painkillers, which are highly addictive,” Jackson noted. “And that can affect a player long after they are done playing. Marijuana doesn’t have those types of effects.”

Howard Bryant, senior writer for ESPN the Magazine, made an even stronger appeal last month to the league to reconsider its policies: “Given that marijuana is a legitimate pain reliever — especially for the migraines that can be a byproduct of head trauma — and is far less dangerous and potentially addictive than, say, OxyContin, it is almost immoral to deny players the right to use it.”

Bryant’s mention of head trauma is significant. In light of the lawsuits that former players who’ve suffered concussions have brought against the NFL, the league should be especially interested in marijuana’s potential to diminish the long-term effects of brain injuries.

As it turns out, recent studies are starting to contradict the notion that marijuana kills brain cells. Last year, researchers at Tel Aviv University in Israel gave low doses of THC, one of marijuana’s primary cannabinoids, to mice either before or after exposing them to brain trauma. They found that THC produced heightened amounts of chemicals in the brain that actually protected cells. Weeks later, the mice performed better on learning and memory tests, compared with a control group. The researchers concluded that THC could prevent long-term damage associated with brain injuries. Though preliminary, this is just one of many promising studies exploring marijuana’s benefits for the brain.

So, are diminishing pain and potentially protecting brain cells enough to convince the NFL that players should be allowed to use marijuana? Not necessarily. For some, the same old refrain — “What about the children?” — still reigns. For example, former Broncos tight end Shannon Sharpe says the league’s policy will never change “because of the way kids follow what NFL players do.”

Sorry, Mr. Sharpe, but kids who idolize NFL players are already bombarded by beer ads, the contracts for which enrich team owners and, by extension, players. And alcohol is objectively more harmful than marijuana in terms of its damage to the body, its addictiveness and its association with violent behavior. If players use marijuana out of the public spotlight to alleviate their pain or to simply help them relax or sleep during a stressful season, society won’t crumble.

The NFL’s current 10-year collective-bargaining agreement was adopted in 2011, so changing its marijuana policy would take some maneuvering. That said, opportunities do exist. For example, it was reported last summer that the league wanted to work with players to increase penalties for driving under the influence of alcohol. Stronger penalties for DUIs in exchange for more lenient policies for marijuana use seems like a fair trade-off for all sides.

Not acting will only delay the inevitable. During the span of the current collective-bargaining agreement, it is likely that many more states will make marijuana legal. Instead of waiting, the NFL should address the issue now so that players can derive the benefits of the substance — or simply use it as an alternative to alcohol — sooner rather than later. steve@vicentesederberg.com

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