At the University of Colorado, Dr. Peter McGraw runs the Humor Research Lab, a group that tries to empirically prove what’s funny and what’s not. In the aftermath of Hurricane Sandy, his group researched a trend: when is too soon to joke about tragedy?

“We found that those jokes started to rise in humor and peaked at about 36 days,” McGraw told host Ricky Camilleri in a HuffPost Live conversation Thursday. “And then what we found was something interesting: with the further passage of time, then humorous responses decreased. There’s sort of sweet spot there.”

The Sept. 11 attacks, however, hold a bit stronger stigma with society than Hurricane Sandy. McGraw joined a three-person panel Thursday on HuffPost Live to chat about how pop culture has helped us appropriately find humor in 9/11, and whether humor on the topic is appropriate at all.

“The job of the comedian is to take some sort of everyday things that happen and put them into context and make it funny in order to send some sort of message or to lighten the mood or to have some sort of commentary,” Amer Zahr, an Arab-American comedian, said. “9/11, like any other phenomenon that would happen in society, is not immune from artists from speaking about it and trying to say something about it that and have some sort of artistic value.”

Matt Wilstein, Los Angeles bureau chief for Mediaite, agreed. Wilstein wrote a list in 2011 for the Huffington Post of post-9/11 comedy milestones, including this Louis C.K. clip.

“It took time after 9/11 for people to be able to make fun of these things,” Wilstein said Thursday. “These were milestones of people figuring out ways to deal with terrorism and 9/11 as comedic points of view.”

Catch the rest of the clip above, and watch the full HuffPost Live conversation here.

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