5
some undetermined source which was not any of the clothing either
of the deceased or of the a pellant. These fibres, from both sources,
were subjected to chemical tests and to examination under both
transmitted light and polarised light. The nature of all these
tests was somewhat complicated and it involved comparison with
control samples of fibres from other simlar materials but Mr. Edgley's
basic finding, resulting from the many tests he carried out between
the 15th of April and the end of that moth was surmarised in an
answer given by him in exam:.nation-in-chief which appears at page
368 of the record :
"A. Yes, I believe as a result of the examination
of finding and comparing fibres from the victim's clothing and those from the suspect that these findings show that contact had taken place between the suspect's sweater, P.25 and the clothing of the deceased- of the victim; and this opinion is based on examining numerous articles of clothing where I have not seen a similar combinatiɔn."
After considerable discussion between counsel, and following the
retirement of the jury to permit further debate and the taking of
evidence from Mr. Edgley in their absence on the question, Mr. Edgley
was permitted to state his finding in the language of probability
statistics. The discussion was somewhat abstruse and certain books
relating to such statistics were cited by counsel but in the upshot
it would appear that it was Mr. Edgley's opinion that, at a very
conservative estimate, and basing himself both upon searches which he
had made for the purposes of this case and similar searches made in
the course of his forensic experience prior thereto, the likelihood.
of discovering on any two items of clothing by chance, and excluding
contact between those two items, a combination of fibres similar to
the identical combinations found on the girl's clothing and on the appellant's sweater was con.iderably in excess of one in one hundred thousand. That in simplest terms would appear to mean that the chances are one hundred thousand to one against finding such a combination on two garments by chance. It should be noted that this answer (See page 382 of the record) was base? solely upon the colour combination and it did not have regard to the fact that the fibres examined by the
various chemical and other tests and whether they came from the
accused's clothing or from the girl's T-shirt show a strong similarity