The idea that "scumbag" criminals shouldn't have lawyers flies in the face of the very reason why we have such a good justice system.
Everyone has the right to a defense. There are countries where you are tried and put in jail, or killed, for something that you said, because you are a threat to the government, because you are a political opponent etc...
It's vitally important, for everyone, that the worst criminals have a fair trial, and usually that means that they need a lawyer.
If we lived in a world where the worst criminals don't get lawyers, eventually we would see people who aren't criminals denied legal defense. It's all of nothing.
I'm not saying that the justice system can't be criticized, but the solutions that people suggest here would make any of us vulnerable to an un-just justice system. And to suggest that Political Correctness is what stops us from hanging thieves? What do you even understand political correctness to be? If someone stole my bike, I would not want them hanged, and political correctness has nothing to do with it.