Tuesday, 16 June 2015

The expert witnesses (part 1)

"The expert’s role is to assist the court in understanding and assessing the evidence on scientific or technical issues. The expert should be reminded that his duty is to be objective and impartial toward the court and is paramount to any obligation he may have to the party that hired him or who is paying for his services. Moreover, the expert’s role is not under any circumstances to be substituted for that of the judge, who has the sole responsibility for assessing the evidence ."

The Blais-Létourneau trial suffered from no lack of expertise and no dearth of expert witnesses.

Sixty-six trial days were spent allowing Justice Riordan to hear the considered opinions of the 16 experts hired by the defendant tobacco companies and the 8 experts engaged by lawyers representing Quebec smokers.

In his ruling on the case, made public 2 weeks ago, Justice Riordan identifies those experts whose opinions were used to substantiate his decisions, and those whose opinions he found unreliable. Sprinkled among his decisions are a few hoist-on-their-own petard moments, when the judge uses the testimony of defence experts to support his findings against the companies.

A quick look today at his receptiveness to the experts in two subject areas - "common knowledge" and addiction.

The "common knowledge" historians

There were no fewer than 6 witnesses brought to court to help establish what the public knew about the harms of smoking and when.

Three of these were historians:  David Flaherty (left) and Jacques Lacoursière (centre) testified for the defence, and on behalf of the plaintiffs, Robert Proctor (right) offered a criticism of this historical approach.

Mssrs. Flaherty and Lacoursière testified that the date at which one could say Quebecers knew about the disease and addiction risks of tobacco ranged from the mid 1950s to the mid 1960s. They based their opinion on a systematic review of newspaper articles and other circulated material. 

The failure to consider the potential impact of advertising on public knowledge and David Flaherty's changing explanations for this exclusion did not sit well with the judge. 

"They seem to have been tracing their opinions with a scalpel in order to justify sidestepping such an obviously important factor. In doing so, they not only deprive the Court of potentially valuable assistance in its quest to ascertain one of the key facts in the case, but they also seriously damage their credibility."

But even the underlying premise that public knowledge could be gleaned from newspaper reports was something the judge did not buy into. "Professor Flaherty talks of "common knowledge", but all either he or Professor Lacoursière is showing is the level of media attention given to the issue. That is not knowledge. That is exposure."

Although he did not "give any credence" to their reports with respect to common knowledge of Quebecers, Justice Riordan nonetheless used their reports to establish when the companies would have known about these issues. This was double whammy for the defence - their famous "common knowledge" historical defence not only failed to help the companies, it was used against them.

Justice Riordan's use of Robert Proctor's criticisms of the "common knowledge" defence is not the only area in which this American historian's impact in the ruling is found. His views on when the (American) public was aware of the harms of smoking and addiction was one that Justice Riordan ultimately adopted for Quebec.

The survey experts

Other experts who testified about "when" the public knew about the harms of smoking were survey specialists Raymond Duch and Claire Durand (left and middle, for the defendants) and Christian Bourque (right, for the plaintiffs). 

Justice Riordan made no complaints about the credibility or credentials of any of these three, but neither did he accept their findings without making his own adjustments. 

Raymond Duch had reviewed the findings of Gallop and other survey firms and concluded that by the mid 1960s people believed that smoking may cause cancer. This was not a high enough level of awareness to satisfy the law when a dangerous product is involved, said Justice Riordan. "The minimum acceptable level of awareness should be much higher than that, for example, 'is likely' or 'is highly likely'." 

After making "reasonable adjustments" to allow public opinion "to move from 'may cause' to 'is highly likely'," he found that the views of Rayond Duch and plaintiff witness Robert Proctor were "consistent". Quebecers did not know about the harms of smoking until the late 1970s and not about addiction for a further 20 years. Mr. Duch's testimony was thus used to validate a "knowledge date" some 20 years later than the defence intended when they brought this witness to court.

Christian Bourque's conclusions were also used in a way not foreseen during the trial. He had used Imperial Tobacco's surveys to ground his opinion on what the public knew and when. After listening to the "vociferous" and "uncontradicted"  and "ill-focused" criticisms levelled by Mr. Duch and Ms. Durand, the judge decided to "exclude the Internal Surveys as a source of reliable information as to the actual knowledge of the general public".

Nonetheless, he accepted Mr. Bourque's report as proof of "what ITL perceived and believed, accurately or not, about the public's knowledge of the dangers of smoking."   That the company did nothing to inform consumers even as it believed that smokers were unaware of the harms was decried by the judge as being "so far outside the standards of acceptable behaviour that one could not be blamed for branding them as immoral." 


Justice Riordan's ruling on the addiction issues in the trial were briefly discussed here last week.

These were informed by the submissions of three experts on addiction: Dr. Juan Carlos Negrete (right) testified for the plaintiffs and the defendants experts were Dr. Dominique Bourget (centre) and Professor John Davies (left).

Those who watched or read the testimony will not be surprised that the views of these last two were heavily discounted by the judge.

British psychologist John Davies' iconoclastic approach to addiction was one that Justice Riordan could not put faith in. "[163] Professor Davies is very much a man on a crusade, too much so for the purposes of the Court. He has a theory about drug misuse and he defends it with vehemence. ... [it] is inappropriate and counter productive for an expert witness..."

Nor could he rely on Canadian psychiatrist and frequent expert witness, Dr. Dominique Bourget, about whom he seems to regret having qualified. "In hindsight, despite her extensive experience testifying in criminal matters, we have serious doubts as to her qualifications in the areas of interest in this trial." 

Dr. Negrete's "occasionally dramatic language" may not always have been to the judge's liking, but his analysis that nicotine diminished ones ability to stop smoking, and that nicotine addiction sets in about 4 years' of smoking, was one that he accepted. "[O]n all matters dealing with dependence, the Court prefers his opinions to those of the two experts in this area called by the Companies."

Moreover, Dr. Negrete was the last man standing after the two addiction experts chosen by the defendants flamed out. "Earlier, the Court held that it cannot rely on the expert reports of Professor Davies and Dr. Bourget. Consequently, the only proof of the effect that tobacco dependence has on individuals is provided by Dr. Negrete."

Of the 6 defence experts who testified in the areas of addiction and common knowledge, the credibility and capacity of 4 were found wanting.

In the coming days, a look at the experts in epidemiology and disease.