The genesis of the medical expert witness could well be considered legally insane. Jokes aside, this idictment is just as true as it
is absurd. History has the tale.
Anglo-Saxon law had no need of expert witnesses until the McNaughton rule needed an expert witness to convey to the court an opinion
as to the sanity of the defendant. Expert witnesses more ably guided the court and jurors as to what they could not see in their
watching of the defendant. During the 1800 high treason trial of James Hatfield, with a brilliant and successful defense of
insanity, Thomas Erskine recounted to the learned but untutored court, his prior case of an incarcerated person seeking release from
a mental hospital. For most of the day Erskine had tried to establish the petitioner’s continuing malady, only to be foiled by the
petitioner’s appearances to the contrary. Then a noted physician chanced to walk into the courtroom. He was immediately able to
establish that the patient believed himself to be Lord and Savior of Mankind and quite insane. The procedure illustrated to the
High Court, the necessity of expert witnesses in their court system. The genesis of the need for expert witnesses comes from the
court’s call for their assistance in cases of alleged insanity. The date of this genesis in Anglo-Saxon law is 1800.
The commencement of expert witness bias dates back to the virtual beginning of expert witnesses in court. In an 1840 high treason
case for an 18 year old who aimed and fired a pistol at King William IV, the defense was insanity. A leader in a society opposed to
the death penalty became the defense counsel. He chose expert witnesses known to harbor causes in opposition to the death penalty.
During trial, they admittedly formed their opinion of his sanity ‘based upon more humanitarian [considerations] than scientific
principles’. From those who interviewed the incarcerated defendant in his later years, it seems evident that it was agenda that
found him insane. Their bias, aside and apart from the defendant’s mental status, governed their expert opinion.
While there were other such efforts to procure judicial reform, early legal commentators thought the bias of the expert witness
doctors stemmed from the sense of professional power, the prestige accorded to, and by, the courts and money. Historically and
currently, physicians have been more motivated by the persuasion that their knowledge should be shared for the public good. There
is little evidence that there has been an enhancement of professional power or prestige. On the contrary, expert testimony has more
often put professional power and prestige at risk, appeal of income aside.
Dr. Louis Dyll