Persons of skill and matters of opinion: the making and rise of the expert witness in English common law 1763 – 1800

Thesis

This thesis challenges the accepted historiographical narrative regarding the origins of the partisan non-medical expert witness. While the expert witness is generally accepted to have been formalized by the courts in 1782, I instead reveal, by novelly turning to patent law beginning in 1763, a rich yet unformalized culture of participation by persons of skill. Patent law uniquely encouraged the participation of experts, as all parties involved in the dispute were, as inventors, experts in their own right. Moreover, the explanation of their inventions at trial begged deference to alleged subject-matter experts.

I show that once jurisprudential weight was placed on the instructiveness of the patent specification, the technical description filed with a new invention, the determinative impact of the testimony of expert witnesses only increased. By 1777, the effect was a tacit acceptance of the hired expert witness who explained the details of the specification to the jury and attempted to sway the jury on their client’s behalf.

Plaintiffs, particularly the first generation of industrialists, quickly discovered the persuasive power of the expert witness. With industrial empires that depended on the enforcement of their patents, they zealously worked to secure increasingly prominent natural philosophers to defend the validity of their property rights at trial. Similarly, plaintiffs and defendants, due to the adversarial and zero-sum nature of law, were incentivized to hire expert witnesses in what quickly became an arms race. From the perspective of the expert witness, I show that presentational ability was of ever-increasing importance, as the art of swaying a jury was as much one of relevant technical knowledge as it was a rhetorical art. That is to say, the emergence of the expert witness was simultaneously the emergence of the expert expert witness.

Authors: Aizenman, AM

• Alternative title: The making and rise of the expert witness in English common law, 1763 – 1800
• DOI: 10.5287/ora-nyw61kman
• Type of award: DPhil
• Level of award: Doctoral
• Awarding institution: University of Oxford
• Language: English
• Keywords: jury trials; English history; law; King’s bench; testimony; partisan expertise; Sir Henry Gould; Dollond v. Champneys; English patent law 1750-1800; James Watt; English reports; Bart.; Boulton & Watt v. Hornblower and Maberley; archival minded legal history; standards of evidence; Iardet v. Johnson; Richard Arkwright; courtroom demonstrations; Sir Francis Buller; natural philosophers in the courtroom; Folkes; Arkwright v. Mordaunt; adversarial law; Arkwright v. Nightingale; civil law; sense perception; Dollond v. Watkins and Smith; John Smeaton; theatrics in the courtroom; Boulton and Watt v. Bull; V. Chadd and others; William Murray; expert witness; patent specification; Lord Mansfield; Rex v. Arkwright; Wells Harbour
• Subjects: History of the English Industrial Revolution; Intellectual Property Rights; English Legal History; History of Technology; History of Science; History of Invention; History of the Long 18th Century; History of Patent Law; History of Epistemology; History of Expertise; History