Mayella does not understand the rules of the court, and so the judge is lenient with her. More than this, however, her "igonorance" encompasses life itself, for she does not have the strength to resist her father's violence against her, and she has grown up not to respect herself. She craves loves so much that she breaks rules of society to find it, as Atticus says, to the one man who had been kind to her, Tom. Everyone in town feels sorry for the Ewells, just as they disdain them. The family has never lived by the rules, and Bob Ewell takes advantage of this. They live past the dump, outside even the margins of orderly behavior, and the judge, rightly or wrongly, takes advantage of all this. Besides, she is a white woman, even if poor and ignorant, and accused of being raped by a black man, which automatically gives her special privileges.
In chapter 18, Atticus questions Mayella on the stand. She is as nervous as her father had been on the stand. Atticus is polite but thorough, and Mayella's struggles to keep her story straight.
Mayella is questioned about her father, as well. She tries to explain that he is fine unless he drinks. There are times that she seems as if she is going to break down and tell the truth, but she does not.
When Atticus questions her as to why no one heard her scream, and tries to get her to admit it was her father that beat her up, Mayella starts to cry. She tells Atticus that all the social niceties, calling her ma'am and such, are not going to get her to say what Atticus wants. At this point she breaks down into sobs, and refuses to answer any more questions.
Mayella's lack of knowledge of the legal protocols expected of her was evident at this point.
"I guess if she hadn't been so poor and ignorant, Judge Taylor would have put her under the jail for the contempt of court she had shown everybody in the courtroom." (188) Because Mayellla was ignorant of the rules she was breaking, it would serve no purpose to charge her with contempt of court, and there would be no one to come forward with money to bail her out.