Free Expert Witness by Anna Sandiford Page B

passages; the new technique involves a few minutes, a lidded test tube and a brush. Much cheaper, quicker and therefore much more likely to be used. Another example is recently completed research that looked at how knives cut through clothing that is well worn (as opposed to new fabric). A simple bit of work but it will help deal with those difficult questions a sharp barrister might ask about the differences between stab tests being undertaken on a new pair of jeans instead of jeans that had been worn for months, like the ones forming the exhibit in a case.
    The successful conclusion of a case often lies in how much money can be spent on it, not on the limitations of science or police ability — an uncomfortable truth but that’s the reality of modern day police work and forensic science. Many people will consider that it isn’t ethical or right for modern society to place a monetary value on crime investigation, but like it or not, that’s just how it is; same as it is in the health services, hospitals, child protection services, fire services, refuse collection, in fact all publicly funded organisations. When I worked in England, there was a seasonal lag in drug trace cases in the second quarter of the year because the police budget had run out and the new one didn’t kick in until April.
    If we take a crime such as murder by gunshot, the numberof personnel involved is enormous — and all of them have to be paid: initial police attending the scene, ambulance crew, pathologist plus mortuary assistant(s) to conduct the postmortem, police officers involved with the case with sometimes several officers in charge of the crime scene if it’s a large one, with one officer per body and an exhibits officer to coordinate item collection, logging, tracking, several crime scene examiners, finger print examiner(s), ballistics expert(s) and toxicologists to analyse and interpret results from blood and other body samples.
    Then there’s the cost of scene equipment, with disposable items such as scene suits, bootees, gloves, face masks, chemicals, evidence bags, transfer of the body to mortuary, hospital costs, sample analysis costs, courier or transfer costs (exhibits and items from scenes have to be transported by secure means in order to ensure continuity of the item and continuous chain of custody) — the list rolls on, even before we get to the cost of legal services, the courts, judges, etc. It’s all a hugely complicated, money-spending machine that is vital in order for you and me to sit at home and feel a modicum of safety.
    What I plan to do in this chapter is briefly discuss why we bother to examine the science at all, what makes an expert an expert in what they do and why it’s important that an appropriate expert is instructed.

    Purely for argument’s sake, let’s say there’s such a thing as a straight forward murder case. While I’ve never had the experience of working with such a case, it should be pretty obvious that shooting another person in the heart is generallygoing to result in the heart owner’s death — we can all understand that. Why then would we bother to examine the science?
    Well, some times questions arise from this sort of death such as how far away would the shooter have been to cause that injury; could Weapon A have caused that injury; how quickly would the deceased have died? All these questions have an impact on determining the circumstances of the death, which is crucial to under standing what happened and who, if anyone, was to blame or was at fault. So back to the original observation that everyone knows shooting another person in the heart usually results in death — while we know what happened on a superficial level, it requires an expert to talk about the detailed mechanics of what exactly happened, which often tellingly includes how and when it happened.
    In the circumstances of our straight forward murder we’d need a