The medical and scientific evidence in alleged tubocurarine poisonings. A review of the so-called Dr. X case

Abstract

The problem of proving the presence or absence of a poison in a buried cadaver is the central theme of this presentation. Certain general questions are posed which may serve to guide those seeking to determine the cause of death in buried cadavers and allegedly due to a poison. Medicolegal and scientific evidence is presented from the court records of five deaths which were alleged homicides due to intravenous tubocurarine. As to the medical evidence: The prosecution claimed absence of adequate medical causes but full congruence with intravenous tubocurarine as the cause of death. The defense claimed and presented its evidence, including history, clinical picture, gross and microscopic pathological findings — for the deaths having occurred from competent natural causes in all but one case. In that one case the cause was undetermined. In two of the four cases evidence was presented for the mechanism of death and why they died at the time that they did. As to the forensic toxicological evidence: The prosecution claimed qualitative identification but with no particular quantitative detection or identification limits of tubocurarine in the remains based on results of combinations of HPLC followed by RIA and of some selected ion direct inlet mass spectrometry. The defense corroborated — along with a quantitative estimate — the presence of a substantial concentration of tubocurarine in the liver specimen of one case. However the chain of custody of this particular specimen was compromised for a period of several days between post-exhumation autopsy and submission to the prosecution toxicologists. With respect to all the other specimens examined by the defense, direct inlet mass spectrometry failed to show ions which are critical for establishing the identity of tubocurarine. The defense also presented results of experiments which showed that the tissues of the cases in question destroyed tubocurarine at such a rate that no reasonably conceivable administered amount could have survived the 10 years of burial of these cases. In each of the five cases exhumation and re-autopsy would have been found to be neither justified nor even indicated had an objective examination of the available record been made and supplemented by a similarly objective review of the literature and the simple stability experiments used by the defense. After an 8-month trial, the jury brought in a not guilty verdict on all counts after less than 2 h of deliberations.