Though its plot focuses on a single moral choice, that of Mrs. Hale and Mrs. Peters deciding whether or not to expose why Mrs. Wright killed her husband, Trifles is thematically complex. It addresses the abiding issue of justice and contemporary issues of gender and identity politics. Susan Glaspell’s power comes from the way she interweaves these issues until they are impossible to separate. When they enter the farmhouse, Mrs. Hale and Mrs. Peters are there as wives, adjunct to their husbands’ roles in society. However, through the process of attempting to help another woman by gathering items from her household that might comfort her in jail, they learn to identify themselves first as women and only secondarily as wives. Each woman recognizes her own life in Mrs. Wright’s suffering, and each comes to see that given the wrong circumstances, she, too, would have killed the man that so damaged her. These women symbolize all women, and this growing awareness suggests the possibility of personal transformation that decades later emerged in feminist consciousness-raising groups. When they decide to hide the evidence of Mrs. Wright’s motive for the murder, the two women are condoning the crime, or declaring that it is not a crime, but justice for the suffering that John Wright inflicted on his wife.
This stance creates a tremendous moral dilemma. The ideal of justice is that a truly just society is impartial. All the male characters are blind to what is going on and are even condescending to the women. The county attorney is the worst example of this. He is so certain that he knows what the situation entails that he will not even let other characters finish speaking. Yet, he and all the male characters cannot see the truth that is literally right in front of their faces. Mr. Hale and the sheriff cannot see that the women they live with are keeping something from them. This suggests that the entire concept of justice is flawed. Either there are different justices for different groups, according to their experience of the world, or, worse, there are different realities, invisible to those who do not share them. The choice to hide a dead bird may symbolize the death knell for the Western political system: How can a fair and functioning society be constructed in such circumstances? At the very least, the play casts doubt on all existing legal structures unless the female perspective is integrated.