prosecutorial misconduct
US legal term for prosecution conduct that denies a defendant a fair trial
Prosecutorial misconduct is a US legal concept covering unlawful or unconstitutional conduct by the prosecution that undermines a defendant's right to a fair trial. The term belongs to American law and has no direct equivalent in Danish legislation. The federal standard is that the conduct must "infect the trial with such unfairness as to make the conviction a denial of due process" — that is, the proceedings must be so fundamentally compromised that the resulting conviction violates the Due Process Clause of the US Constitution.
The most frequent form of prosecutorial misconduct is the withholding of so-called exculpatory evidence — material that favours the defendant. The duty to disclose such material to the defence follows from Brady v. Maryland (1963), in which the Supreme Court held that a prosecutor's deliberate suppression of exculpatory evidence violates the defendant's constitutional rights. Breaches of this Brady obligation are among the most thoroughly documented causes of wrongful convictions in the United States.
Other forms of misconduct include presenting evidence the prosecutor knows to be false or misleading, the use of false testimony, improper influencing of witnesses, and serious procedural violations during the trial. What they have in common is that they can make a fair verdict impossible and thereby pave the way for an innocent person to be convicted.
When a convicted person invokes prosecutorial misconduct as grounds for appeal or reopening of the case, it must as a rule be shown that the prosecutor's conduct was not merely erroneous but had decisive significance for the outcome. In cases where DNA evidence or other new information has subsequently exonerated convicted persons, investigation has often revealed that the prosecution actively withheld or distorted evidence.
In the federal system, the wilful violation of a person's civil rights under colour of public authority can potentially be prosecuted criminally under 18 U.S.C. § 242. In practice, however, criminal prosecution of prosecutors is rare; the most common consequences are the overturning of convictions, disciplinary proceedings before bar authorities and, in some cases, civil claims for damages.
