How does Mrs. Peters attempt to maintain objectiveness with Mrs. Hale when she concludes Minnie's innocence?

Mrs. Peters says that they have no way of knowing who really killed the bird. "I knew John Wright," Mrs. Hale replies grimly. Mrs. Peters says in defense of the dead man, "It was an awful thing was done in this house that night, Mrs. Hale…Killing a man while he slept-slipping a thing round his neck that choked the life out of him."