Dean Wigmore once wrote that the hearsay doctrine is the “most characteristic rule of the Anglo-American law of Evidence.” Today, it can be said that the character evidence doctrine is the most characteristic rule of American evidence law. At early common law, a proponent could not introduce evidence of an accused’s uncharged crime in order to show the accused’s bad character and, in turn, treat that character as proof that the accused committed the charged crime. Modernly, most legal systems in the common law world have significantly relaxed that prohibition. However, with few exceptions, the evidentiary codes in the United States firmly maintain the prohibition. For example, Federal Rule of Evidence 404(b)(1) provides: “Evidence of a crime, wrong, or other act is not admissible to prove a person’s character in order to show that on a particular occasion the person acted in accordance with the character.” Thus, at an armed robbery trial, the prosecution may not introduce evidence of a prior, uncharged robbery by the accused simply to show that the accused is a robber and hence more likely to have perpetrated the charged robbery.