本研究主要是陳述自白濫用之困境與解決途徑。過去法院在審理案件時，相當重視犯人的自白，然而過份強調自白容易違反無罪推定原則及公平法院原則，且易造成誤判。自白信用性應如何確定，一直是刑事法學及偵審實務上最具爭議且影響事實認定之重大的課題，但深入探討此議題的文獻有限。在台灣最著名的冤案之一就是江國慶案，其冤案成因，主要是法院與偵查機關過度依賴江國慶的自白，研究者為監察院調查官，於民國92年奉命調查此案，調查期間因案件需要，遂開始研究此議題。拉丁法諺明確說明「自白是證據之王」。過去常見使用非任意性自白作為裁判基礎，但對於如何獲取自白方式較不被重視，使用酷刑取得非任意性自白很常見。雖然現代社會使用拷問及酷刑方式取得非任意性自白並不多見，但法官與檢察官仍十分重視自白，因與其他證據相較，自白較容易勾畫犯罪事實之全貌，具有較優勢的地位。雖然自白之取得縱未經強暴、脅迫、利誘、詐欺或其他不正方法，然仍有許多案件顯示有虛偽自白情形。到底是何種原因產生虛偽自白，應該用何種分析方式與審查標準評價該自白，首先必須探討國家機關獲取自白之方式與過程對於犯罪嫌疑人心理影響，始能明瞭自白內容其實是偵訊者透過訊問與犯罪嫌疑人溝通互動之產物，存有偵訊者主觀的意念。因此，本研究之目的主要是藉由江國慶案件深入分析自白信用性，並訂定出審查標準。 本文引用日本有關自白信用性之學說、研究結果以及現行實務，配合我國實務現狀，再藉由江國慶案卷證，描繪自白信用性審查標準。江國慶案因受限軍事審判法規定，不得上述上訴最高法院審酌，其中有關江國慶自白部分具有相當疑義，包括自白之成立係在高壓偵訊環境中所生, 自白與證物不一致等。本案為密室偵訊之典型案例，其中雖自白任意性之爭議極大，但因任意性舉證極為困難，導致歷審軍事法院均三言兩語駁回被告有關任意性之調查證據之聲請，此即為自白任意性在實務操作最大的問題；就自白信用性部分，歷審法院認定方式較無標準，這也是我國實務上之通病。綜合文獻及實務，研究者認為在審查自白信用性的標準應包括：(1)自白成立過程 (2)自白內容變動之合理性 (3)體驗供述之陳述 (4)秘密的暴露 (5)自白與客觀證據之一致性 (6)可供證實之物證不存在與欠缺相關情況證據 (7)犯罪嫌疑人對犯行前後偵訊者以外之人言行與被告的辯解等7項標準。 希望藉由本研究所訂定之標準，提供從事司法實務者在審判審案件時有一清晰客觀的標準，以達成維護公共福祉與保障人權。 / The focus of this study was to describe the dilemma regarding the abusive use of confessions and its solution. In the past, a great emphasis has been placed in course on the confessions of the accused. However, an overemphasis on confessions may violate the principles of presumption of innocence and just court, resulting in miscarriage of justice. Determining the credibility of confessions has been one of the most controversial issues in the criminal law and in the investigation and trial practice. However, limited studies have explored on this issue. In Taiwan, one of the most well-known cases of injustice is the case of Chiang Kuo-Ching. The primary reason for the injustice was the over-reliance of the court and investigation agency on the confession of Chiang Kuo-Ching. As an inquisitor at the Control Yuan, the researcher was involved in the investigation of the case of Chiang Kuo-Ching in 2003. During the investigation, the researcher began a more in-depth study on the issue of abusive use of confessions. Latin law principles proclaim that “confession is the king of evidence”. Involuntary confessions have been commonly used in the past as a foundation for judicial judgment. However, the strategies for acquiring confessions were not stressed. Torture was used in the past for the acquisition of involuntary confessions, while it is not a current practice. Currently, judges and prosecutors greatly value confessions due to their greater capacity of providing an overall picture of the criminal facts, as compared to other strategies. In many cases, false confessions are commonly present. To understand the causes of false confessions and to develop standardized determining criteria for false confessions, it is critical to explore the psychological impacts of the processes and strategies of acquiring confessions on the criminal suspects. Such exploration will provide an understanding that a confession is the product of the interactive communications between the investigator and the suspect, involving the subjectivity of the investigator. Therefore, the purpose of this study was to analyze the credibility of confessions and to develop an evaluation criteria based on an analysis of the case of Chiang Kuo-Ching. A Japanese theory of credibility of confessions, research findings, current practice in Taiwan and the case of Chiang Kuo-Ching were used to develop credible evaluation criteria for confessions. Due to the restriction from the military trail law placed on the case of Chiang Kuo-Ching, appeal to the Supreme Court was not permitted. Several elements of the confession of Chiang Kuo-Ching were questionable, such as the highly stressful interrogation environment for the confession, and the inconsistency between the confession and evidences. The case of Chiang Kuo-Ching is a typical case of secret interrogation, which generates great controversial on the voluntary nature of confessions. Due to the difficulties in obtaining evidences for voluntary confessions, the requests to acquire evidence for voluntary confessions were denied by the military court. This is the greatest problem related to the practical operation of voluntary confessions. Currently, there are no standardized evaluation criteria to review the credibility of confessions, which has been a common issue in the practical judicial operation. Derived on the literature and practice experiences, the researcher proposed the application of seven criterions in the evaluation of the credibility of confessions: (1) process of acquiring confessions, (2) rationality of changes in the contents of confessions, (3) existence of criminal experiences, (4) exposure of secrets, (5) consistency between the confessions and objective evidences, (6) lack of evidence to proof the crime of the accused, and (7) the words and actions of the suspect toward the individuals other than the investigators before and after the crime, and the argument of the defendant. The finding of this study will provide an objective and standardized criteria for judicial practice for the purposes of protecting public welfare and human right.