June 6, 1990: 2 Live Crew Declared Legally Obscene
A Federal judge in Florida ruled that 2 Live Crew's As Nasty As They Wanna Be LP, featuring heartwarming ditties like "Me So Horny," Dick Almighty," and "If You Believe in Having Sex," was legally obscene. Which, of course, made them really popular.
On a related note, this same week in 2003 a High court judge in London, England ruled that rap lyrics should be treated as a foreign language because he was unsure of what "shizzle my nizzle" and "mish mish man" meant. He was overseeing a copyright violation claim between two rival rap groups.