最高法院近來在許多判決裡，將嚇阻警察違法偵查視為證據使用禁止的基礎理論，並由此推論出，除了強暴、脅迫所取得之供述以外，原則上容許使用私人違法取得之證據。然而，嚇阻違法偵查觀點係奠基於當事人進行主義之上，不適用於我國仍受職權調查原則支配的刑事程序，也不符現行法的法定證據使用禁止規定，故無助於釐清私人違法取證之證據使用禁止難題。本文認為，迄今並無任何觀點能夠有效地將證據使用禁止效果連結到私人取證的違法性，國家能否使用私人違法取得之證據，應依法院調查證據對於被告基本權之干預是否具有合憲性事由而定，私人取證的違法性對此合憲性判斷並無特殊意義。 Recently, many Supreme Court cases have been of the opinion that the ratio legis behind the exclusionary rule of evidence is to deter future illegal conduct on the part of the police. It follows that evidence illegally obtained by a private person is admissible in principle with the exception of verbal statements collected by means of coercion or intimidation. However, the deterrence rationale derived from the adversarial system is neither applicable to our criminal procedures where the court examines the evidence ex officio nor in conformity with our current statutory exclusionary rules. Therefore, such a rationale is not able to clarify the dilemma on whether evidence obtained illegally by a private person could be admissible in court. This paper argues that since there is no basis for applying an exclusionary rule of evidence to evidence obtained illegally by a private person, whether such evidence should be suppressed in court depends on the courts evaluation on whether the violation of the defendant’s constitutional rights can be justified.