This is mostly attributed, according to web sources, to Rodney King in a public appearance after his LAPD experience: "People, I just want to say, can't we all get along?" Over the years, and in different venues (songs, articles, etc.) it has been slightly changed from time to time to what you posted. Btw....wasn't til I looked this up that I remembered Rodney died at the young age of 47! Ciao!