[3] French historian and sinologist Jacques Gernet has called the Tang Code "an admirable composition of faultless logic in spite of its size and complexity.
"[3] The American sinologists Wallace Johnson and Denis C. Twitchett described it as "a very rational system of justice" in which "both the accuser and the officials involved had to be careful lest they themselves face punishment".
While questioning a witness, the magistrate would look closely for five kinds of behavior: "the person's statements, expression, breathing, reaction to the words of the judge, and eyes.
Through careful observation, it was thought that the experienced magistrate could arrive at a knowledge of whether the person was, in fact, telling the truth.
"[6] If a magistrate was unable to decide a case on the basis of evidence and witness testimony, he could seek the permission of higher officials to use judicial torture.