It's certainly happened before:
George Harrison was sued for "My Sweet Lord" as it was a carbon copy of The Chiffons' hit "He's So Fine." Harrison had to pay Royalties.
Same with Ray Parker Jr. theme song of the movie, "Ghostbusters" as it was a note-for-note ripoff of Huey Lewis' "I want a new drug"
Wether intentional or not, these things happen.... and the infringing artist usually winds up paying for it.