Yes, he stood alone. But I'm not as impressed with him as you are. He should have gotten the others on his side so they could give the judge a guilty verdict, like the lead in "12 Angry Men". Had he done that, that psycho would be in prison now and everyone else would be able to move on with their lives.
Wouldn't you need to be able to read to create or select that sign? This would make more sense if the Road Runner said "We can't read" instead of using a sign.