A well know ex-biker group originationg in az/maybe calif. led by pappy for many years. The biker group came to an end around 2000? when the hells angels came to phoenix and ?? something like that.
in the 70's and 80's the dirty dozen had a bad reputation for being a cruel biker gang, scum, criminals, rapists, burglery etc. in the 90's they appeared to have mellowed out (or been killed or imprisoned) and even did some runs to benefit charity's. cancer, children disease etc.
Pappy was the head of the dirty dozen, a sweet old man, when I met him.