In Taiyuan, there lived a household where both the mother-in-law and daughter-in-law were widows. The mother-in-law, in the prime of her middle years, found her loneliness unbearable and began a secret affair with a local ruffian. The daughter-in-law discovered this, felt deeply disgraced, and secretly guarded the family gate, preventing the ruffian from entering the house. The mother-in-law, furious at her intrusion upon her illicit moments, rushed to the magistrate’s office and falsely accused her daughter-in-law of infidelity.

The county magistrate inquired, "Who is the adulterer?" The mother-in-law replied, "The man comes early and leaves late; I do not know who he is. But my daughter-in-law certainly knows. Bring her in for questioning, and the truth will be revealed." The magistrate summoned the daughter-in-law, who, when questioned, vehemently asserted that it was the mother-in-law who was unchaste and involved with the ruffian. They argued back and forth, neither side yielding ground, making the truth impossible to discern.

The magistrate grew dizzy and ordered the apprehension of the ruffian for interrogation regarding the matter. The ruffian proved even more cunning, stating, "I do not know these two women; it is clearly a case of animosity between mother-in-law and daughter-in-law, wrongfully framing an innocent man." The magistrate roared, "There are hundreds of men in the village; why choose to frame you and no one else? Guards, flog him!"

The ruffian, under the torment of the punishment, repeatedly begged for mercy and blurted out a lie: "I confess, I confess! The person who sleeps with me is the daughter-in-law." The magistrate nodded, ordered the daughter-in-law to be severely beaten, issued a writ of divorce to dismiss her, and sent her packing from the home. The daughter-in-law, boiling with righteous indignation, traveled to the provincial capital to plead her case. The prefect was hesitant to rule definitively, and the case languished, suspended and unresolved.

At that time, Magistrate Sun Liuxia of Linjin County was renowned for his brilliant judgments and countless solved cases. The prefect specially ordered that the case of the daughter-in-law be handed over to Sun for resolution. The accused were brought before him. Sun Liuxia conducted a brief interrogation, asking only a few questions before having the matter settled in his mind. He ordered the three individuals detained in the prison, to be reviewed again the following day. Secretly, he instructed his subordinates to prepare bricks, stones, knives, and awls, stating they would have a purpose.

The yamen runners were perplexed, thinking, "If torture is necessary, the yamen is fully equipped with various instruments. Why the unnecessary trouble of procuring bricks and stones, of purchasing knives and awls?"

The next day, when the court reconvened, the officers brought the mother-in-law, daughter-in-law, and the ruffian before the hall. Sun Liuxia declared, "This case requires no deep investigation. Though the ** adulteress remains undetermined, the actual culprit is already clear. You two were originally from an upright household, merely misled by a wicked man; the fault lies solely with the ruffian. The knives and stones are here; you may each take them and slay the principal villain."

The mother-in-law and daughter-in-law hesitated, fearful that if they missed their mark, they might ultimately pay with their lives. Sun Liuxia said, "Do not worry, I am here." Hearing this, the two women each seized a stone and hurled it at the ruffian. The daughter-in-law, harboring long-held resentment, lifted a massive stone with both hands, wishing to see the ruffian instantly killed. The mother-in-law used only small bricks and stones, aiming only for the ruffian's buttocks and legs, places of no consequence. Her blows were light, and she dared not strike at any vital spot.

Sun Liuxia then ordered them to use the knives. The daughter-in-law plunged a blade deep into the ruffian’s chest, while the mother-in-law clutched the handle, merely posturing, daring not to stab for real. Sun Liuxia waved his hand to stop them, saying, "I now know which ** woman is the true adulteress." He ordered his men to arrest the mother-in-law, who, upon severe interrogation and torture, confessed everything without reservation. The ruffian was then given thirty strokes of the cane, and the case was closed.