In 1997, the Yale Law Journal published an article by George Fisher entitled The Jury's Rise as Lie Detector. After tracing common law methods of ensuring testimonial truth from the ordeal, Fisher focused on the moment during the mid- to late nineteenth century when the sacred oath system gave way to the jury as a mechanism of truth assurance. The key innovation at this time was allowing defendants to testify. In the United States, Fisher ably demonstrates, this change in the law of testimony was tied to the inclusion of African-Americans as witnesses.
Fisher's nuanced thesis suggests that the fate of testimonial exclusion laws was determined by the political battles surrounding the treatment of freedmen that followed the Civil War. The Northern states wanted the South to abandon its testimonial exclusion of blacks. While "it is unclear why Northerners shunned the more obvious strategy of attacking the Southern racial exclusions as racist," they chose to argue against the disqualification of witnesses as a matter of evidentiary theory. This broad-spectrum assault left the North open to a tu quoquedefense: Southerners merely pointed to the North's continued exclusion of defendants as invalidating the North's attack. By accepting the more general Benthamite critique of competency rules, the North opened itself to Southern accusations of hypocrisy. Northern politicians even adopted this attack on occasion: In an 1862 speech, Senator Foster of Connecticut claimed that Massachusetts still excluded atheists and, thus, that Charles Sumner's amendment to allow blacks to testify in federal courts was hypocritical. According to Fisher's thesis, these predominantly Southern responses forced Northern states to eliminate their own competency rules in order to force the South to do the same. Fisher's research demonstrates a remarkably neat historical connection between the North's disavowal of exclusion laws and the South's repudiation of the often-paired bans on defendant and African-American testimony. He convincingly argues that this confluence was not accidental, that the North was hoisted on its own rhetorical petard and forced to abandon its exclusionary laws. Fisher shows that once the tu quoque defense became unavailable, the South followed suit, resulting in the widespread elimination (or at least severe limitation) of testimonial exclusion throughout the United States.
Kaufman, Paul W.
"Disbelieving Nonbelievers: Atheism, Competence, and Credibility in the Turn of the Century American Courtroom,"
Yale Journal of Law & the Humanities: Vol. 15
, Article 5.
Available at: https://digitalcommons.law.yale.edu/yjlh/vol15/iss2/5