3 ideas
Under the imperial legal code, a magistrate needed the accused's own confession to convict. The investigation therefore aims less at proof than at the moment the suspect breaks. In the strange-corpse case, an exhumation finds no marks of violence and Dee is left exposed to punishment for a false accusation. He then stages a mock tribunal of the underworld to frighten the widow into confessing.
Most gong'an fiction names the criminal early, so the suspense lies in how justice is delivered, but this novel hides the guilty party until the magistrate deduces it. That choice lets the reader weigh clues alongside the judge. Moral judgment and supernatural elements remain part of the story.
Dee's cases overlap rather than running strictly one after another, though the double murder is solved before the bride's death is reported. He leaves the tribunal in disguise to gather testimony people would not give a magistrate in open court, while trusted assistants pursue other leads, and he turns what they learn in the field into formal court proceedings.