Suppression of evidence is a term used in the United States legal system to describe the lawful or unlawful act of preventing evidence from being shown in a trial. This could happen for several reasons. For example, if a judge believes that the evidence in question was obtained illegally, the judge can rule that it not be shown in court. It could also refer to a prosecutor improperly or intentionally hiding evidence that he or she is legally obligated to show the defense. In the latter case, this would be a violation of the 5th amendment to the United States Constitution. This can result in a mistrial in the latter case and/or the dismissal of the prosecutor.
If the discovery of an item(s) was obtained by illegal means, it may still be allowed into evidence under some circumstances. These exceptions include:
Evidence obtained as a result of Miranda violations is also subject to special analysis, depending on whether the statement is deemed voluntary or coerced, not merely whether police provided the appropriate warnings.
CPS in the uk suppress evidence http://stanw965.wix.com/misscarge