What is the theme in Blood Relations by Sharon Pollock?

Truth is a major theme in the story. The question is raised what is truth? The Actress asks, "Did you do it?" A question to which Lizzie does not - or cannot - respond. Emma asks her regularly, a litany each day. "Did you - did you - did you?" And Lizzie is again mute. Throughout the play there are more questions raised than answered. The audience would expect empirical evidence, and the play produces the Defense attorney who questions the suspect and her maid. But their authenticity, their authority are in question because the events are being recounted by Lizzie. By presenting the evidence of the case through the memory of the accused, there is no certainty that the events portrayed are real or are figments of Lizzie's imagination.