Eric Colvin

Fairness and equality in the criminal process

It is sometimes contended that evidence obtained in an unfair way should be liable to exclusion, even if it is reliable, in order to protect the accused’s right to a fair trial. This paper examines two main questions. First, what kind of theory of investigative fairness might underlie claims that evidence has been obtained unfairly and that this investigative unfairness could lead to adjudicative unfairness? Secondly, which factors will make claims for investigative unfairness stronger or weaker? The paper does not seek to resolve the questions of whether and when evidence should be excluded because of investigative unfairness. Questions respecting the exclusion of evidence have generated the paper. Its primary focus, however, is on dimensions of the law of criminal investigation rather than the law of evidence itself. A preliminary distinction might be drawn between two different types of argument for excluding reliable evidence because of how it was obtained. One is that exclusion will advance the general public interest in criminal investigation being conducted in certain ways; the other is that exclusion will vindicate some right of the particular accused such as a right to fair treatment. A utilitarian calculation of the public interest might sometimes call for the exclusion of evidence of acceptable probative value because it was obtained in an unlawful or improper way. That, however, would be a different matter from recognising any claim that the accused deserves to have the evidence excluded. When evidence is excluded on grounds of public policy, the accused is merely an incidental beneficiary of the way in which the public interest is pursued. In contrast, what the accused actually deserves is at stake when exclusion is sought in order to vindicate that accused’s rights.1