Imagine that a gay man made a move on a friend, who was so offended by the sexual connotation that he killed the gay man in a fit of rage. Instead of being charged with murder, the charge was downgraded to manslaughter, since the unwanted homosexual advance apparently provoked the friend to murder.
This is no hypothetical, it's a legal argument known as the homosexual advance defence and it was used in Queensland just last year. The case involved a man who was beaten to death by two acquaintances after he apparently made sexual advances to one of them. The homosexual advance defence also remains admissible in law in NSW.