About: Silent witness rule

The silent witness rule is the use of "substitutions" when referring to sensitive information in the United States open courtroom jury trial system. An example of a substitution method is the use of code-words on a "key card", to which witnesses and the jury would refer during the trial, but which the public would not have access to. The rule is an evidentiary doctrine that tries to balance the state secrets privilege with the bill of rights (especially the right of the accused to a public trial, and the right to due process). In practice the rule has been rarely used and was often challenged by judges and civil rights advocates. Its use remains controversial.