Judge Taylor is mentioned in chapter 9 and appears in chapters 16 through 21.
The first time Judge John Taylor is mentioned is in chapter 9. Atticus mentions that he was chosen by Judge Taylor to defend Tom Robinson, and he has been granted a postponement in the trial.
You know, I'd hoped to get through life without a case of this kind, but John Taylor pointed at me and said, 'You're It.'" (ch 9)
Judge Taylor made a careful choice in choosing Atticus. He knew that Atticus would actually defend Tom, unlike most people. He chose Atticus because he wanted Tom to be defended.
In chapter 16, Judge Taylor is “looking like a sleepy old shark” when he is on the bench. Scout describes him as “amiable, white-haired, slightly ruddy-faced” (ch 16) and “must have been nearly seventy” (ch 17) and Atticus said he was “a good judge” (ch 18).
[He] was a man who ran his court with an alarming informality- he sometimes propped his feet up, he often cleaned his fingernails with his pocket knife. (ch 16)
Although he seems to be asleep, Judge Taylor is actually alert during trials. He is very good at his profession.
He was a man learned in the law, and although he seemed to take his job casually, in reality he kept a firm grip on any proceedings that came before him. (ch 16)
During the Robinson trial, Judge Taylor is more active than in most cases. He is “relaxed” but vigilant. He runs the trial carefully, and makes sure he does not have any interruptions. He keeps order well, and the trial goes reasonably smoothly.