| 
| 
| 
| 
| 
| 
| 
| 
Opinion Papers and Publications
Representing Canada
in IUPHAR
| | | | | | | | | | |
||
| pharmacologycanada | Opinion Papers and Publications |
Representing Canada in IUPHAR |
The Pharmacologist As Expert Witness As pharmacologists we recognize the prominent role played by drugs in the treatment
of disease. We can feel justifiably pleased with the way that the continuing evolution of
pharmacology has brought many life-threatening illnesses under control and improved, in
no small measure, the quality of life. There can be little debate about the significant
benefits that pharmacology has brought to society. As pharmacologists we are also aware
that drugs can be hazardous. We know that side-effects from drugs, or the taking of
excessive doses can be, in fact, quite damaging to an individual's well-being. While we often
describe adverse outcomes form misapplications of drugs in terms of medical exigencies,
there is another important arena where drugs affect peoples' lives, namely, the interplay
between drug effects and the legal system.
Given the prevalence of drug use in society it should not be too surprising that people who take drugs are well-represented amongst those who are charged with criminal offenses. The drugs in question may be ones prescribed by a physician, ones bought and used as "over the counter" medications, or others, whether legal or illicit, which were purchased for non-medicinal purposes. Quite commonly, the drugs have psychoactive properties. Not uncommonly, mixtures of such substances may have been taken. In virtually all instances, the individuals were arrested because of an illegal act which brought them to the attention of the police. In preparation for a trial it is the obligation of an effective defense lawyer to see whether the use of drugs by a client may have contributed to the crime. Criminal offenses generally require proof by the Crown of a physical act accompanied by a specified intent. The ingestion of drugs may have rendered the accused incapable of forming the requisite criminal intent. Alternatively, the degree of ingestion may be the point in dispute, as in a charge of exceeding a blood ethanol concentration of 80 mg/dL while driving a motor vehicle. The lawyer may well seek this information from a pharmacologist. The approach will most likely be that you receive a call from the lawyer. Details, often incomplete at this time, will be provided and your views sought as to whether there is merit to obtaining an expert opinion. At this time you should consider whether your professional specialization will allow you to eventually provide a solid, substantive response, or whether the lawyer should be referred to another party. The initially provided details often require expansion before a full reply can be provided. If ethanol is the substance of concern, the key issues may require estimations of blood alcohol concentrations at particular times. If so, you will require information on the physical characteristics of the accused individual, age, height, weight, sex, particulars about the recent consumption of alcohol - what was ingested and the pattern of consumption over the time when the drinking took place, when and possibly what quantity of alcohol was consumed prior to this drinking period to determine whether there could have been residual contributions of alcohol from the earlier time that overlapped with the more recent drinking. Other necessary information will be the specific times of interest, usually the time when the police first observed the lawyer's client and times when any breath analyses were conducted. To fill out the background information, you should find out when and what the accused ate, whether any other drugs were taken prior to or concurrent with drinking, whether the individual has any disease or disorder that might affect the absorption or metabolism of ethanol or the ability to provide a valid breath sample for analysis and what the regular drinking pattern of the individual is. In instances where other drugs are involved you should receive generally comparable data. The person's physical characteristics are often less relevant in these instances, but you will need to know what substances were taken, what dosage regimens were being used and how long they had been in place so that the possible development of tolerance can be considered. If you are able to obtain any information on the individual's responses to earlier exposures to the drugs it may prove useful, as would be any indication of factors likely affecting absorption or elimination of the drugs. When you have obtained the necessary background, you can begin to assemble your response. The details of the case should now be complete and you should be considering how the formulation of an opinion can be developed. Toward this end, you should review and become thoroughly familiar with the current state of knowledge about the drugs involved in the case. In most instances a written report will be required. It is essential that you identify the foundations for your opinions from both the facts that have been provided and any suppositions you have incorporated. You will be dealing with the various points from a hypothetical perspective and the lawyer may well have you declare the basis for the assumptions in court. Be thorough, but err on the side of brevity and limit the use of professional jargon. As a concluding statement, invite the lawyer to call you if any clarification of points you make is required. If the report casts a positive view, you may well be required to appear at a trial to give evidence, vice voce. Generally, notification as to when the trial will be held will come several weeks ahead of that time. Make sure that the trial date is satisfactory and virtually unencumbered by other demands. The scheduling can often be altered to a more convenient time if a conflict is identified. You will soon find out that trials do not adhere to a strict timetable and there is a very strong likelihood that you will not be giving your evidence until late in the assigned day. Do take a number of papers or minutes of meetings to read when you are not engaged in listening to evidence from other witnesses or in giving your opinion. The lawyer may well wish to meet with you to review the presentation of your evidence. Some of the questions which have been prepared in advance may be scientifically unsophisticated, depending on the familiarity of the lawyer with the pharmacological- toxicological topics at hand, in which case your input may not only be valuable when it comes to answers, but can be helpful in redefining the questions themselves. The process of a trial allows both the prosecution and defense to present their cases before a judge (and jury) in a progressive and logical order. In criminal trials the prosecution produces the evidence first and the defense cross-examines witnesses. In the second stage the defense provides the witnesses with their evidence in chief and the prosecution cross-examines. It is of value to listen to the evidence from both sides as it occurs so that you can see how it corroborates the material supplied earlier. Thus, while other witnesses may be required to leave the courtroom before giving their evidence, so that their contributions are independent of prior testimony, an expert witness can usually stay to hear the whole story. It is always pleasant to hear the accumulating data parallel the factual circumstances used in your opinion. If this does not occur, you should be prepared to alter your opinion. The testimony given under oath by witnesses at the trial carries considerably more weight than any earlier statements. It is the evidence that any opinion must be based on. Naturally, an substantive changes should be related to the lawyer at the first opportunity. After you are sworn in, the lawyer who has retained you will have to qualify you by defining for the judge the area of expertise being addressed. Towards this end you should have provided the lawyer with a copy of a current curriculum vita. To assist the process, a copy of this may be given to the court as an exhibit. You can be called upon to say where you acquired your expertise, through training, research, or other professional activity. T his may be pursued in some depth, either in reply to the lawyer who seeks your expertise, or to questions from the opposing counsel. Ultimately, your acceptability as an expert able to provide relevant opinion evidence rests with the presiding judge. As you given your testimony under oath and in chief, you will be responding to questions from the lawyer who sought your opinion. You will have some insight into this set of queries from earlier practice. Consider that your audience is intelligent and worldly, but has not profited from a course in pharmacology. Give your answers confidently in a clear, concise manner, avoiding as far as possible scientific terms that are enigmatic or esoteric. When it is necessary that you elaborate on the scientific underpinnings, think that you are explaining the issue to an interested layman. It is important that at the end of this session all parties follow how you arrived at your opinion and what it is. Keep your testimony within the boundaries of your expertise and tied to evidence which has been presented. Do not speculate on other scenarios unless this is accepted by the judge and the limits have been established. Your testimony will now be probed in cross-examination by the opposing lawyer. As this lawyer has not received the benefit of a pre-trial review, the questions asked may well be less clear-cut. The objective of this cross-examination is to pursue any weaknesses existing in your account, whether there are variances in the information used in arriving at your opinion, or whether there are legitimate differences in the scientific assumptions that have been applied. In total, they aim at reducing the weight of your opinion. While the queries may be more obscure as they probe for frailties, you should be fair and professional in reply. You have provided a scientifically valid opinion which relied on the credibility of the information it was based on. If this is called into question you can agree that your conclusions could have been modified if other circumstances had applied. If an alternate scientific premise is raised and you are able to reply, then do so. If the reference is made to a specific article which you know, then you can comment directly. Conversely, if you were not aware of it, then say so. That will usually end the matter. You will not be expected to do a critique of a novel reference under the pressure of cross-examination. After this examination has finished, the judge may have some questions to ask. Some important point may have been omitted, or clarification is sought. Again, reply as the expert you are. Both lawyers will then be asked if they have any further questions which have arisen from the judge's questions. If they have none then you have finished. If you wish to leave the court then you should have asked the lawyer to request this of the judge when your contribution has ended. Alternatively, if this was not done, then ask the judge if you can depart. Otherwise, you should return to the audience until the remaining elements of the trial take place. It is quite enlightening to hear the concluding summations of the two lawyers as they refine the pieces of evidence that support their positions and deal with portions which are more blemished, and how points of law are raised for the judge to consider in reaching a verdict. Thereafter, the judge will deliberate and provide the final result, and reasons for judgment. All will now have commented on your evidence. You may well be quite surprised to hear how your contributions have been interpreted. On your way out it is worthwhile reflecting on your participation. As revealed by the summaries, did you convey your meaning so that it was truly understood? Might there have been a simple analogy that could have assisted explanation of a difficult point? In essence, you have participated in a teaching exercise. You have prepared and conveyed information. The efficiency of that transfer has been revealed promptly before your eyes. What grade would you give yourself? Hopefully, it will be a good one. Return to Documents Page |