what does Hale mean when he asks if every defense is an attack upon the court? How has Hale changed by the end of this act?

The hysteria is working to the court's advantage. People defending themselves only makes them more culpable (guilty) in the court's eyes. THe court is actually looking for people to defend themselves, it gives the court more material to condemn them with. By Act 3 Hale has seen the absurdity of the court. He now knows that the proceedings are all a sham. The court only wishes to legitimize itself by hunting innocent people for witchcraft.