Why does the Idlers' club outside the courthouse object to Atticus's defending tom robinson?

Question

Book: to kill a mockingbird

Answer 1

because blacks didn't have the same rights as caucasions in the days that the book is set.

Atticus's defense of Tom Robinson provoked peoples ire because of this.

Answer 2

because Atticus is a well respected member of the community and the fact that he is defending a black man in that day and age, and in that part of the world, and the fact that he is defending him properly is like omg! you just don't do it