This is a good question...consider who her "peers" are.  In this time period, women were expected to be at home, keeping quietly busy with the household dynamics and child rearing.  When the men come to the Wright house to investigate Mr. Wright's death,  they are assumed to be her peers.  We also understand that Minnie Wright is facing charges of murdering her husband and that she will face an actual jury...probably also men.  As we continue to read, we notice that the men don't pay attention to certain things...the cracked fruit jars, the quilt pieces, the empty birdcage...they are all dismissed as "women's things"--more clearly, silly trifles that aren't important.  However, on closer reading, they are the ONLY things important in the story.  The women come to understand that Minnie most likely DID murder her unloving husband who took a happy girl who sang and was lovely to everyone and stuck her in a cold, isolated home away from her friends...and KILLED her bird.  The women quietly decide to hide the most damning evidence...the small canary's body wrapped in a special piece of cloth hidden in her sewing box...from the men.  Without it, Minnie probably won't be convicted.  Therefore the real peers are the women who come to pick up items Minnie has requested...most importantly, her apron, by which she now defines herself.