To make the Parents Music Resource's infamous "Filthy Fifteen," a song had to have focused on sex, violence or drugs – at least according to those long-ago guardians of public morals.

The PMRC, co-founded by future Vice President Al Gore's wife Tipper, published the list in 1985, recommending that each of these songs be banned because they were the most egregious. Most of them, it's no surprise, were rock songs – specifically, hard rock or metal songs.

So, AC/DC, Motley Crue, Judas Priest, Twisted Sister, Black Sabbath and W.A.S.P. are all duly represented in the above list. Click through for the complete run-down on which tracks were targeted.

By the way, the PMRC also pushed for a ratings system, similar to the one in place for movies, and were successful in getting warning labels affixed to the front of singles and albums that record companies agreed were explicit.

It all came to a head during an explosive congressional hearing on Sept. 19, 1985, in which Frank Zappa, Twisted Sister's Dee Snider and John Denver testified before the Senate Commerce, Science and Transportation Committee on the matter. Album covers by Def Leppard and W.A.S.P. were mentioned, as was Twisted Sister's "We're Not Gonna Take It" and Van Halen's "Hot for Teacher."

Fast forward a few decades, and the parental advisory sticker has become a relic. There were those who felt from the beginning that it encouraged sales among rebellious youth. The advent of downloading and streaming services led to the warning sticker's complete obsolescence.

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