NFL Comissioner Roger Goodell, left, and NFLPA Executive Director DeMaurice Smith. (Phil Long/Associated Press)

IRVINE, Calif. — The NFL has written to the NFL Players Association offering to work in tandem to study the potential use of marijuana as a pain management tool for players, according to people familiar with the situation.

It is the clearest indication to this point that the league may be willing to work cooperatively with the union toward such marijuana use, which is currently banned by the sport.

The NFLPA is conducting its own study and, according to those familiar with the deliberations, is yet to respond to the NFL’s offer to cooperate on marijuana-related research.

“We look forward to working with the Players Association on all issues involving the health and safety of our players,” said Joe Lockhart, the NFL’s executive vice president of communications.

The NFLPA did not immediately respond to a request for comment.

The NFL, according to one person with knowledge of the matter, wrote a letter to the union asking if, given the NFLPA’s public comments on the issue this year, it is interested in working together on research. The league’s letter outlined a few areas for potential research that included pain management for both acute and chronic conditions.

The union previously has indicated that it is, on its own, studying marijuana as a pain management tool and, in what it considers a separate but related issue, holds interest in making further changes to the league’s rules regarding recreational marijuana use by players.

DeMaurice Smith, the NFLPA’s executive director, told Washington Post reporters and editors in January that the union was preparing a proposal to the league that would result in a “less punitive” approach to recreational marijuana use by players.

“I do think that issues of addressing it more in a treatment and less punitive measure is appropriate,” Smith said then. “I think it’s important to look at whether there are addiction issues. And I think it’s important to not simply assume recreation is the reason it’s being used.”

The union separately formed a pain management committee to study, among other things, marijuana as a pain management tool for players. The committee is technically a subcommittee of the NFLPA’s Mackey-White traumatic brain injury committee.

“How do you make sure that you address any potential addiction issue? Because I’ve read the literature on both sides,” Smith said in January. “How do you deal with the fact that some people are using it purely recreationally and pivoting it to … people who are using it medicinally either as a pain eradicator or a stress-coping mechanism? So what we’ve decided to do is, to the best we can, look at it as related but nonetheless separate issues. Do I expect in the near future we are going to be presenting something to our board on the first issue? Yes.”

NFL players currently are tested for marijuana and face potential discipline, including suspensions, for positive tests.

The league and union agreed in 2014 to modifications of the drug policy regarding marijuana. The threshold for what constitutes a positive test for marijuana was relaxed. A level of 15 nanograms of THC (tetrahydrocannabinol) per milliliter of urine or blood was counted as a positive, the most stringent standard in professional sports, before 2014. Under the revision, 35 nanograms per milliliter counts as a positive; a nanogram is one-billionth of a gram.

“We’ve had several conversations about this issue and several years ago we did take a less punitive approach to marijuana,” NFL Commissioner Roger Goodell said in a Fox radio interview in January. “That will be one of the subjects in the collective bargaining process, which we’d like to get into sooner rather than later.”

The union has not delivered its proposal regarding a less punitive approach to marijuana use by players to the league since Smith’s comments earlier this year, according to multiple people close to the situation. One reason, according to one of those people, is the feeling that the league prefers to deal with the issue as part of negotiations for the next collective bargaining agreement, rather than as a separate issue. The current CBA between the league and union runs through 2020.

The two sides previously attempted to negotiate a separate agreement on another meaningful issue — the sport’s system of player discipline and Goodell’s role in it — but a deal collapsed at the last minute. That issue is unlikely to be negotiated further between the two sides until the CBA deliberations.

Stephen Jones, a Dallas Cowboys executive and a son of Cowboys owner Jerry Jones, said last weekend at the team’s training camp in Oxnard, Calif., that it is difficult to determine whether such issues should be bargained separately or negotiated only within the context of a potential CBA extension.

“It’s a great question,” Jones said. “I think it’s a debated question. Some people feel strongly we should address it now. I think some people feel that we’re close enough that you should wait and take care of it in one fell swoop when you sit down and bargain with the union. There’s people who would love to have an extension. I think both sides would probably love to have it. … To me, personally, it’s one opinion, I think whenever there’s things that ought to be looked at, I think you ought to address them. I know Jerry feels that way.

“But at the same time, I’m certainly respectful and understand that a lot of times these things — player discipline, in particular — when it comes to things that deal with the players are usually taken care of with a broad stroke within the CBA. It’s a tough one to answer. It’s not just marijuana. The whole thing always has to be looked at. … I just want to make sure that we’re doing everything the very best way because that’s what people expect [from] the NFL is to be the best in class.”

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