Since no one seems to doubt that Mrs. Wright killed her husband, how does this story create suspense?

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.