本文選擇以白居易作為唐代的一位「知識人」進行考察。通過他為參加「書判拔萃科」的科舉考試所模擬的「百道判」，分析他對唐律的理解與詮釋。 「百道判」是為應考「書判拔萃科」而作的練習題，其中頗有以模擬的獄訟案件，或經學、史籍所載的概念、掌故或史事，假設兩難情境之議題，續以判詞論述，從而展現其對於維護禮教倫理和法律秩序的態度與看法。 本文大致就「百道判」中直接涉及「純粹法律類型」的判進行分析，以闡述其推理與論述。白居易判詞的法律推理，明顯有以下幾個特色值得注意：一、重視違法事實的釐清。二、注意罪刑輕重的區分。三、採取「息訟」、「無訟」的態度。四、兼顧儒家禮教與法律規範。

This research paper is to inspect Bai Jü-Yi, as an intellectual, in Tang Dynasty. From Bai Jü-Yi’s Bai-Dao Legal Precedent to analyze the appreciation and explanation of Tang Code. Bai-Dao legal precedent, was written by Bai Jü-Yi, is an exercise in composition after he passed the preliminary. There are some topics included it, for example historical records, annals, anecdotes, and conceptions. From its explanation, it developed the opinion and attitude of the morality and the order of law. The constructions of the Bai-Dao legal precedent were divided into four categories. The first category is the criminal cases. The second category is the conjunction between the Confucianism and the law. The third category is the order under the Confucianism. All the other cases are included into the fourth category. This research paper will discuss the first category about the criminal cases. The Legal Reasoning of Bai Jü-Yi’s Legal Precedent has some characteristics as following: The first is to attention on the legal elements; the second is note of the distinction between misdemeanor and felony; the third is the pursue the attitude of none litigation; and the four is taking into account between the Confucianism and the law.