The question of whether Nora's actions are morally justified in A Doll's House by Henrik Ibsen is one of ethics. Different ethical systems evaluate different types of behavior in different ways. Under, for example, a pure deontological systems, such as that of Christianity or Immanuel Kant, her behavior would be consider indefensible, something one could claim that the play illustrates in the way that one lie generates additional lies, leads to blackmail, etc. From the point of view of eudaimonian ethics, Nora's lie may have contributed to her well-[being because it sets her on a course that leads to self-realization. Existentialist ethics would approve of her final commitment to authenticity, whatever the cost, and admire her crime as the test that leads to her final realization:
Torvald--it was then it dawned upon me that for eight years I had been living here with a strange man, and had borne him three children--. Oh, I can't bear to think of it! I could tear myself into little bits!