Trifles is a mystery in the form of a one-act play. The use of this genre allows Glaspell to maintain the narrative's tension and mystery, as the audience's understanding is limited to the real-time actions of the characters on the stage. Further, the one-act play allows Glaspell to use the story as a vehicle for her feminist sensibilities. Glaspell instills her arguments with pathos, confronting the audience directly through her characters' dialogue.
The play is largely comprised of realistic dialogue, which Glaspell uses to build tension and drive the plot. The characters' action is deepened and expanded upon by the stage notes, which Glaspell uses to inject description into the play.
Trifles is also a classic mystery, in which two men and two women explore a murder scene with the hope of discovering the motivation. The mystery centers not on who committed the murder (there is only one suspect) but rather on what her motives were. The real mystery is what drove Minnie to commit so heinous a crime, and to appear so nonchalant after the fact.
The play gains some extra tension when the two women, Mrs. Hale and Mrs. Peters, slowly realize that they are faced with a choice: should they abide by the law and reveal the hidden evidence they uncover? Or should they protect Minnie, a fellow woman with whom they sympathize? The audience watches as the women come to terms with their dilemma, but the question of whether or not they will turn on Minnie is delayed until the end of the play. This, in turn, presents the tension between loyalty to one's sex and adherence to the law—a tension that is deepened by the legal system's disregard for the rights of women during the early 1900s. The feminist overtones of this subplot transform the play from a simple mystery into one that analyzes the complex realities of women's domestic lives in the early 20th century.
