Bill McNue is a called a 'coward' by everyone in town, but no incident is shown that illustrates is supposed cowardice. It just gets mentioned that 'he won't draw a gun' but they don't describe any time when that was actually a problem.
At the final shootout, he doesn't put on his glasses.
Yeah, I know, he has his shadow back, but, wtf, he is supposed to hardly be able to see.