The suspense in the story is largely centred around whether the men are capable of proving that Mrs Wright killed her husband using the evidence they are presented with, and whether the women will support or betray poor Minne Wright.
Mrs Wright would clearly be seen as guilty, though possibly by reason of insanity with the scant evidence that the men manage to uncover-
"No, Peters," said the county attorney incisively; "it's all perfectly clear, except the reason for doing it. But you know juries when it comes to women. If there was some definite thing--something to show. Something to make a story about. A thing that would connect up with this clumsy way of doing it."
The suspense is in whether Mrs Hale and Mrs Peters will abide by the laws of the state or the laws of femininity: whether they are 'married to the Law' or have a sense of justice beyond the law. The choices they make hold Minnie Wright's life in their hands.
Then Martha Hale's eyes pointed the way to the basket in which was hidden the thing that would make certain the conviction of the other woman--that woman who was not there and yet who had been there with them all through that hour.
The audience is surprised when the women unite to remove the key piece of evidence and revels in their ability to piece together the motives of Mrs Wright's actions which the men remain ignorant of.