I say "original" because Ely was kicked out of the band shortly after the song was recorded in 1963. (I don't think that's him singing in any of the Kingsmen's videos on YouTube.)
From his obit in the Times (my emphasis):
Jack Ely would later insist that as a 19-year-old singing “Louie Louie” in one take in a Portland, Ore., studio in 1963, he had followed the original lyrics faithfully. But, he admitted, the braces on his teeth had just been tightened, and he was howling to be heard over the band, with his head tilted awkwardly at a 45-degree angle at a single microphone dangling from the ceiling to simulate a live concert.
Which may explain why what originated innocently as a lovesick sailor’s calypso lament to a bartender named Louie morphed into the incoherent, three-chord garage-band cult classic by the Kingsmen that sold millions of copies, spawned countless cover versions and variations, was banned in Indiana, prompted the F.B.I. to investigate whether the song was secretly obscene, provoked a legal battle and became what Frank Zappa called “an archetypal American musical icon.”
High school and college students who thought they understood what Mr. Ely was singing traded transcripts of their meticulously researched translations of the lyrics. The F.B.I. began investigating after an Indiana parent wrote to Attorney General Robert F. Kennedy in 1964: “My daughter brought home a record of ‘LOUIE LOUIE’ and I, after reading that the record had been banned on the air because it was obscene, proceeded to try to decipher the jumble of words. The lyrics are so filthy that I cannot enclose them in this letter.”
The F.B.I. Laboratory’s efforts at decryption were less fruitful. After more than two years and a 455-page report, the bureau concluded that “three governmental agencies dropped their investigations because they were unable to determine what the lyrics of the song were, even after listening to the records at speeds ranging from 16 r.p.m. to 78 r.p.m.”
Talk about a waste of taxpayers' money! Where was the tea party then?