Alaska just became the third state to legalize marijuana. John Prine has steadfastly maintained that “Illegal Smile,” one of the enduring classics from his 1971 debut album, was not about smoking pot, despite widespread assumptions to the contrary. “Fortunately,” he sang, “I have the key to escape reality.”

He wrote the song at home in the Chicago suburbs the year of Woodstock and Altamont, as documented on his 1988 album John Prine Live: “It was 1969, and nothing seemed to make much sense to me. I liked to laugh and when I can’t laugh I like to smile. Some people think you should have a reason to smile or they think you’re up to something, so it must be an illegal smile.”

Not everyone believes his innocent explanation for the song’s origins. When he played the song early on for an underground TV show in Chicago, the cameraman kept zooming in on a fake marijuana plant. (The tune would make it to national television a few years later as the improbable theme song for a short-lived sitcom.)

Fast forward a few decades. An aspiring singer-songwriter named Kacey Musgraves – born the year John Prine Live came out – approached Prine before his annual Christmas concert, according to a recent Rolling Stone Country article: “This little girl comes up to me with her buddy…. They wanted to take me out in the parking lot and get me high. I said, ‘Uh, gee, thanks but… no, thanks.'”

Since then, Musgraves has become a fast-rising Nashville star. Her major-label debut, Same Trailer Different Park, has earned her multiple awards, including a Grammy for Best Country Album. Unfortunately, the album didn’t include “Burn One with John Prine,” in which Musgaves sings, “my idea of heaven / Is to burn one with John Prine.”

Recently Musgraves got to do the next best thing, according to the RS Country article: perform with Prine on the annual Cayamo cruise. Here’s a fan’s video of her telling the story and singing “Burn One” as Prine looks on. “Maybe he would sit awhile,” she sings, “and render me an illegal smile.”