The evidence that only the women notice in this excellent play is the dead bird that was obviously killed by John Wright and then carefully wrapped in silk and stored in Minnie Wright's sewing basket. This of course is crucial evidence, because from Mrs. Hale's knowledge of both John and Minnie Wright and what a bleak man that John Wright was, we can assume that John Wright killed the bird. The way that the bird's neck is described as being "wrung" likewise ties in with the way that John Wright himself was killed, which suggested that Minnie Wright, in an explosion of anger, much like the anger that Mrs. Peters felt when a boy took up a hatchet and killed her kitten in front of her. Note what Mrs. Hale concludes from seeing the bird:
No, Wright wouldn't like the bird--a thing that sang. She used to sing. He killed that, too.
Thus it is that ironically the women, through discovering the bird, also solve the crime that the men are not able to find any evidence concerning.