In the 40 years since the debut of Up in Smoke, Cheech Marin and Tommy Chong’s seminal 1978 stoner comedy, cultural attitudes have drastically shifted on marijuana. So when we sat down with the iconic duo, we asked them whether or not they believed their film had played a part in the current (and escalating) nationwide movement to legalize the drug.

“It’s totally responsible for it. We’re ready for our royalties,” proclaimed Cheech, who joined his partner in (fictional) crime in a visit to Yahoo Entertainment (see video above). Moreover, Cheech claims that he became a true believer after he discovered that marijuana soothed his nausea more effectively than any prescription remedy. And now that 29 states have legalized marijuana for medical and/or recreation use, he argues: “We’ve passed the tipping point. The boulder’s rolling downhill now.” Chong agrees, saying that our current anti-marijuana U.S. attorney general, Jeff Sessions, is “the best reason in the world that it should be legal.”

Both a pioneer in representing marijuana onscreen, and one of the funniest comedies of its (or any) decade, Up in Smoke‘s legacy continues to be potent. You can check out the film on its new 40th anniversary Blu-ray set, which is available now.

Watch: Cheech and Chong reveal 5 mind-altering facts about ‘Up in Smoke’:

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