As long as NFL players are not driving, and are not in public, they can consume as much alcohol as they want. Marijuana consumption on the other hand, is strictly prohibited, no matter what. The sad irony of course being that alcohol is very harmful for your body, rotting your organs and causing other health issues. The same cannot be said about marijuana consumption, especially if it's vaporized or consumed in edible form.
Earlier this year President Barack Obama told the New Yorker that he didn't think that marijuana is more dangerous than alcohol. A poll by ESPN asked 82 NFL players if they agreed or disagreed with the President's statements. Per ESPN:
As part of a survey of 100-plus players conducted by ESPN.com's NFL Nation, 75 percent of the 82 players who answered said they agree with Obama's statement, which he made during an interview in January with The New Yorker.
I'm actually surprised that the number for 'agreed' was only 75%. I'd love to hear why the other 25% of poll participants feel that marijuana is more dangerous than alcohol. The poll was released on the same day that the NFL upheld the suspension of Cleveland Browns wide receiver Josh Gordon. Josh Gordon is being suspended for an entire season because he tested 1 ng/ml higher than the NFL threshold for marijuana. The NFL's marijuana threshold is ten times more strict than the threshold for the Olympics.