The climax of the play comes when the women find the body of the bird in the sewing box. It represents the culmination of all their discussions, such as the reasons for the cage door being opened and the nervous style of stitching on Mrs. Wright's quilt. Upon finding the body of the bird, the women were able to piece together all their prior discussions and envision the murder and why it happened. Glaspell's description of their look of realization and subsequent "horror" make this climax.
I am reminded of "The Usual Suspects," when the Inspector realizes that everything Verbal told him, all those random stories, were phony, and suddenly, it all comes together. The two moments are similar: Unimportant, trivial, and almost "trifle" detail leads to something larger and vitally essential.
In the short play Trifles by Susan Glaspell, the climax is when Mrs. Peters and Mrs. Hale find Mrs. Wright's dead bird in a fancy box. Meanwhile, the men are outside trying to find clues and evidence about the murder of Mr. Wright. In reality, the women find the key piece of evidence (the dead bird)--which is more psychological than forensic in nature. The women understand how lonely Mrs. Wright must have been with no children around. Mrs. Hale says, "No, Wright wouldn't like the bird--a thing that sang. She used to sing. He killed that too." The bird's wing has been broken, which is symbolic of the way in which Mr. Wright crushed Mrs. Wright's spirit by stopping her singing and joyfulness. Though the women don't state outright that they excuse Mrs. Wright's murder of her husband, they certainly understand it. At the end of the play, Mrs. Hale hides the box with the bird in her coat, while the sheriff and attorney search fruitlessly for something that would explain the crime. It's clear that the men don't understand why Mrs. Wright killed her husband but that the women absolutely do.