Lawyer Monthly Magazine - July 2019 Edition

JUL 2019 51 Expert Witness www. lawyer-monthly .com the road, but in the home and on holiday. This creates new opportunities and challenges in understanding what matters and what doesn’t. There is a fascinating international debate about the role of cannabis and cannabinoids in traffic safety. The laboratory work consistently shows acute impairment of skilled performance related to safety critical activities but because the cannabinoids are insoluble in water, they disappear from the blood very quickly, so levels are hard to interpret. It isverydifficulttorelate a blood level with impairment. The epidemiological studies show little relationship between levels of cannabinoids and risk of collision or other accidental injury. Many commentators have reached a false conclusion that there is no safety risk. As an expert witness, what are the most common cases that are you typically called upon to do? Themost common request for my expert opinion is to interpret the significance of a blood alcohol concentration in collision, travel insurance claims and personal injury. I have more than 30 years’ experience answering the usual questions: was alcohol a contributing or causal factor in the incident? What was the blood alcohol concentration at the crucial time? What did the person consume to reach the measured blood alcohol concentration? Were they truthful in their account? In most cases, the question I am asked is whether there is evidence that the person ‘under the influence of alcohol’ at the time of the incident. When other drugs are involved, expert opinion can be more difficult. Whilst impairment due to alcohol has been extensively studied, there is much less data for most other substances. The same questions are often relevant: Did the drug contribute to the event? Was the person under the influence of the drug? What did they take? This is particularly important in workplace drug testing where a ‘positive’ result might have an innocent explanation. For instance, could a positive result for morphine in urine be the result of consuming poppy seed bagels? We have had several cases of employees incorrectly facing discipline or dismissal because their positive drug screen was due to poppy seeds in the diet. It takes an expert to determine whether a positive drug screen represents heroin use or consumption of grandma’s poppy seed cake. I am staggered by the number of people whose lives are ruined by poor decisions involving alcohol and drugs. The consequences can be life- long with physical injuries such as quadriplegia or financial ruin. Some of our cases have had millions of dollars in pay-outs resting on interpretation of the facts. Travel insurance claims for treatment in the US for injuries sustained under the influence of drugs and alcohol can run to millions of dollars. Another focus of my work is the interpretation of injury. People in institutional care are often deniedaccess to theprotections of the criminal justice system, especially if they are non-verbal and unable to give an account of what happened. On the other hand, zealous overreaction to an unexplained injury can see a cloud of suspicion and even threats of unemployment unfairly placed on diligent staff members. I have taken pride in seeing justice done whether that means criminal charges when deliberate injuries have occurred or exoneration when signs have simply been misinterpreted. A case in Singapore involved false report of serious assault that could have resulted in an innocent mother being jailed and the complainant incorrectly compensated for self-inflicted injury. My testimony challenged the official police version and resulted in an acquittal. How do you ensure that the expert opinion that you provide is objective? The key to providing expert opinions is to have no investment in the outcome of any proceeding. I see my role as impartially looking at the available facts and providing the best interpretation based on my knowledge and experience. The greatest compliment I received as an expert came from a former Government Ombudsman who said that my reports were conservatively written, accurate and that when I said something, I meant it. Providing expert opinions is humbling, because you know that in every case the opinion “ Many aspects of clinical medicine remain unaltered over time but there have been many technological changes that influence current practice.