Divining the truth is generally seen to be a critical function of legal proceedings. Although factors such as compassion or fairness may be considered when dispensing justice, the truth is the foundation upon which justice is based. The U.S. Constitution, state constitutions, and other federal and state laws contain many provisions designed to increase the likelihood that the truth will emerge during legal proceedings. Primary among these provisions in criminal trials are the defendant's rights to cross-examine witnesses effectively, to confront witnesses physically, and to call witnesses on his or her behalf. Throughout U.S. legal history, there has been a special concern about the use of children as witnesses in legal proceedings, because it has often been assumed that children would provide inaccurate testimony. This assumption led to the exclusion of children from legal proceedings for many years, and then to the presumed incompetence of children, which could be challenged by a party hoping to call a child as a witness (see Wheeler v. United States, 1895).