Disgraceful or inappropriate public behaviour that would never be tolerated from a "normal" person, but is accepted when that person is retarded/disabled.
Johnny Downer (whilst rubbing his genitalia through his dungarees) shouts: "EUEUEEEERRGHHH DO YOU WANT SOME OF THIS YOU DIRTY WHORE?!"
Sexy female 1 (turns, shocked and appalled): "Excuse me?!"
Johnny Downer's carer: "I am awfully sorry, he has Down's syndrome"
Sexy female 1 (embarrassed smile): "Awww, isn't he a lovely young man? Don't worry about it, have a nice day!"
Johnny Downer (with a dirty grin): "I love my retard rights"