The Preparation of Evidence.
“More mistakes are made, many more, by not looking than by not knowing.” You must be ready to meet an exhaustive interrogation in Court: hence it is essential that a careful clinical or post-mortem examination should be made, with the aid of all reasonable modern apparatus, and that what is known professionally concerning the matters in hand should be revised from modern text-books: your knowledge of pathology must be up-to-date. “You must know a thing before you suspect it, and you must suspect a thing before you find it.”
Remember you are not a partisan: value accuracy of observation and of statement as you do your professional reputation.
You must be prepared to explain facts and conclusions clearly to a body of laymen.
Beware of mistaking a previously formed inference for a recollection of actual fact—assumed conclusions sometimes fallaciously suggest the real cause. “The chambermaid, in the background, made out as much of the letter as she could, and invented the rest; believing it all from that time forth as a positive piece of evidence.” Stat pro ratione voluntas is a fallacy to be guarded against.
Welcome, and even suggest, conferences which will avoid subsequent public differences in medical opinions.
Decide what exhibits and sketches you will hand in. Label, initial, and number them. If they are returned to you after the trial, preserve them for possible future use (e.g., pathological specimens).
Previous to the trial keep all notes and exhibits under lock and key.
Remember medico-legal evidence is subject to certain limitations—your “facts” may be absolute, or probable, or merely possible (see p. [45]).
Refresh the memory from your clinical or other notes just before giving evidence rather than when in the witness box.
Any notes read in the witness box are open to the inspection of the Court. They must have been made by you at the time of the event in question, or immediately thereafter.
All clinical notes and personal memoranda should be destroyed upon the death of a medical practitioner, who should see that his Will contains such a direction.