In part, that's a reflection of the way marijuana use is viewed by mainstream society today compared with the way it was viewed the past. It's still illegal, yes, but it's not exactly high on the country's list of potential sins.
A 2006 United Nations report found that more than 160 million people use marijuana annually, and a U.S. government survey found that 83 million Americans have tried the drug at least once. Since 1996, 13 states have legalized it for medicinal use.
Two of the past three presidents, Bill Clinton and Barack Obama, have admitted experimenting with it, and George W. Bush simply declined to answer questions about past drug use. Clinton received more derision for claiming he had not inhaled than for saying he had tried pot. Barack Obama later played off the line, saying: "When I was a kid, I inhaled. That was the point."
Some of this generation's most successful entertainers, from film director Judd Apatow to Phelps' musical favorite, Lil' Wayne, have laced their art with references to marijuana and the culture around it.
And then there are the hundreds of athletes who have either admitted marijuana use or been caught in possession of the drug. From Kareem Abdul-Jabbar to Randy Moss, you could build a Hall of Fame of superstars who have been associated with pot. Santonio Holmes just caught the game-winning pass in the Super Bowl, three months after he was charged with marijuana possession.
Disturbing pattern?
Dorfman said most people will regard Phelps' actions as harmless or at worst harmful only to him.
"There are so many worse things you can do in public, things that affect other people," he said. "I think his DUI was much worse. That could've killed someone."
With two incidents now on his resume, Phelps could seriously hurt his marketability with a third offense, Dorfman said.
Phelps' citation for driving under the influence in 2004, which also came in the months following an intense Olympics, complicates the issue. This is his second public stumble while partying, and when viewed together, it raises the question: Does Phelps party too much?
It's a question some within the world of swimming have privately been asking for several years. Pictures of him in bars and at parties have been popping up on the Internet with increasing frequency in recent years. But at what point does playful fun become an actual concern?
