The voice behind one of the catchiest, messiest recordings in the history of rock n’ roll has passed away. Jack Ely, co-founder of the 1960s frat-rock pioneers The Kingsmen, died on Tuesday at the age of 71. If you’ve ever listened to, or danced like a fool to, the 1963 hit “Louie Louie,” then you know Ely’s voice:

The Kingsmen version of the three-chord song inspired numerous covers by other rock and pop artists—from Frank Zappa to Joan Jett and the Blackhearts. The song has become so popular, there’s even an International Louie Louie Day.

But the most fascinating aspect of The Kingsmen’s “Louie Louie” is that it triggered an FBI investigation, along with national outrage. And it was all, at a very federal level, much ado about nothing.

The infectious sloppiness of the Kingsmen track stems from the fact that when the band stepped into the studio to record the song, the sound engineer had hung the microphone from the ceiling. Ely had to stand on his toes, stare at the ceiling, and essentially scream-sing into the mic. The 20-year-old vocalist was also wearing braces.

As a result, no listener has ever been able to discern what Ely was shouting at the ceiling that day. (Click here for the actual lyrics, written by Richard Berry in 1955, which pretty innocently tell the tale of a sailor and the girl he loves so much.) But that didn’t stop people from trying, and some of those people sensed obscenity afoot.

So, a bunch of concerned listeners started writing the government about how there was this “Louie Louie” tune on the radio corrupting their kids with sexually explicit lyrics. Parts of the song were misheard as, for instance, “fuck your girl,” “fine little bitch,” and “‘I felt my bone, ah, in her hair.”

One especially outraged parent penned a letter to Attorney General Robert F. Kennedy asking him to please think of the children.

“Who do you turn to when your teenage daughter buys and brings home pornographic or obscene materials being sold along with objects directed and aimed at the teenage market in every City, Village and Record shop in this nation?” the hyperventilating letter reads. “The lyrics are so filthy that I cannot enclose them in this letter…This land of ours is headed for an extreme state of moral degradation what with this record, the biggest hit movies and the sex and violence exploited on T.V. How can we stamp out this menace????”

Radio stations banned the song, and the governor of Indiana went as far as to effectively ban the Kingsmen record, around the same time Michigan was considering doing the same. So after the J. Edgar Hoover-era FBI jumped in, the bureau spent two years investigating Ely’s rendition. Two years.

You can read the FBI’s file on “Louie Louie” below. It’s 119 pages, and includes interviews with Kingsmen members and the songwriter. As part of the hard-hitting investigation, bureau employees listened to the rock n’ roll song many times, at different speeds, in their attempts to determine how raunchy it was.

Eventually, the FBI gave up and determined that this “Louie Louie” business was in fact, “unintelligible at any speed.”

The federal investigation was, of course, a waste of time and resources. It did, however, increase the popularity of the song, and amused Ely greatly.

“The song beings as an obscure rhythm n’ blues B-side in 1957 and, by the end of the story, becomes everything from a theme song for the Leukemia Society of America to a song for people marching 100,000-strong through Philadelphia while playing kazoos,” music critic Dave Marsh wrote in his aptly titled book, Louie Louie.

Not half-bad for an allegedly smutty rock song that was once investigated by J. Edgar Hoover’s minions.