I would begin my answer by briefly explaining the context in which the play was written, which would help to bring together the two halves of the question. Priestly wrote the play a year after the end of the Second World War, where he had the seen the issues of class divisions firsthand, and used the play to bring these ideas to light for the wider public. With the Birlings representing the worst shortcomings of the middle classes, exemplified in the year in which Priestly set the play (1912), and Eva Smith representing the working classes they exploited, the stage is set for a drama which encapsulates both the personal and more universal consequences of their actions. When continuing to answer the question, I would show how Mrs. Birling is not only responsible for Eva's death in her actions and attitudes, but how these condemn the class she represents. To do this I would not only examine her use of language but also the stage directions, how she speaks with dignity and is agitated by the revelations about her family in relation to Eva, terrified of her perfect world coming crashing down. I would examine her role throughout the acts in chronological order, and it is important to note that the end of the play sees Mrs. Birling as proud and uncaring as before. She refuses to accept her responsibility despite the Inspector’s prophetic warning and instead feels ‘ashamed’ of the others’ actions. Her dismissal of the night’s events cements her representation of a selfish middle class, with her final line, 'In the morning they’ll be as amused as we are', showing that she hasn’t learned her lesson and doesn’t care for the terrible consequences her actions have wrought. Not only did Mrs. Birling help destroy Eva’s life but her actions and attitudes do her, and her class, more harm than good.