Lyric discussion by BrainDamage 

George wrote this song merely as a humorous social satire, but it unfortunately took on another role and meaning. At the time, the so-called counter-culture adopted the song as its anthem against police. It became further notorious when Charles Manson, in his very disturbed mind, believed the phrase "a damn good whacking," meant against the American police. During the murders of Sharon Tate, the LaBianca's and others, knives and forks were used to stab them, because these utensils were mentioned in the song, and the words "pig and piggy," were written with the victims blood on the walls. Naturally Harrison was horrified when he learned his song took on another meaning. It was meant to be a simple commonplace song, and the line "damn good whacking," actually came from a suggestion from George's mother, when he asked her for a word that rhymed with backing and lacking. It had nothing at all to do with American police.

from iamthebeatles.com

BrainDamage is right about the Manson murders. Also I think it was the Tate murder that they wrote in blood on the wall "Political Piggy" to make it look like a group like the Black Panthers had actually done the murder. The song is about dirty politicians. People often confuse the term 'Pig' a derogatory term for a police officer with the term 'Piggy' a term for a corrupt politician. Easily mistaken. The fact that the politicians are 'Piggies' in this song and the line 'Clutching forks and knives to eat their bacon' would mean that intern the politicians were...

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