In February 2014, the Supreme Court of Canada released its decision in R. v. Sekhon 2014 SCC 15. It’s a case which involved the importation into Canada of 50 kg of cocaine. Border officers found the stash in a concealed compartment in a truck Mr. Sekhon was driving. The compartment was opened by a fob in Mr. Sekhon’s possession.

Mr. Sekhon was charged with importing cocaine and possessing it for the purpose of trafficking. He was convicted based in part on the evidence of a police officer’s opinion evidence about blind couriers (also known as blind mules). Mr. Sekhon appealed, first to the BC Court of Appeal, then to the Supreme Court of Canada. The result? Seven judges of the highest court said some aspects of the police officer’s opinion evidence about blind couriers was improper.

What are blind couriers?

They are people who are unknowingly used by others to carry drugs. It’s one reason airport notices warn about leaving your bags unattended.

The Crown witnesses at Mr. Sekhon’s trial included a senior police officer who had been involved in about 1,000 cases of importing cocaine over his 33-year career. The police officer testified as an expert on some aspects of the drug trade and provided his opinion about certain evidence in Mr. Sekhon’s case. When the police officer was testifying the prosecutor asked him about blind couriers. Ever encounter any blind couriers in those 1,000 cases? The answer the police officer gave? He’d heard of them, but never had one in any of his cases. In other words, the police officer testified there is no such thing as blind couriers.

The trial judge convicted Mr. Sekhon of importing cocaine and possessing it for the purpose of trafficking. In doing so, he relied partly on the police officer’s evidence about blind couriers.

Fast forward: five of the seven appeal judges at the Supreme Court of Canada decided the trial judge was wrong to do that. However, they also said it wouldn’t have changed the conviction. So, no new trial, Mr. Sekhon. The other two appeal judges disagreed with their colleagues on this aspect of the case. They would have given Mr. Sekhon another day in court.

Why do we need expert opinion evidence?

It can be invaluable. Used appropriately, it helps a judge or a jury understand the significance of certain evidence. It must be relevant. It must be necessary to help a judge or a jury. It must not be inadmissible for some other reason. And, it must be given by a properly qualified expert.

In cases involving cocaine importation, police officers routinely give expert opinion evidence. They can provide insights about the evidence based on what they’ve learned through training and experience. In such cases expert opinion evidence can really assist a judge or a jury. But, the judge must still do his or her best to ensure that the expert’s testimony remains within the proper boundaries of expert evidence.

Police expert opinions in drug cases aren’t technical or scientific

This is significant. It means police expert opinions in drug cases can’t be challenged in the same way as expert opinions about technical or scientific subjects. For example, you can’t challenge police experts about whether they arrived at their opinions through appropriate technical or scientific procedures. For the most part, the opinions of police experts are based upon on-the-job experience. For this reason alone, it’s very important for trial judges, prosecutors and defence lawyers to ensure they don’t allow the opinions of police experts to substitute for the decisions a judge or a jury has to make. Decisions about things like whether the accused person knew he or she was carrying drugs.

So what was the problem?

In Mr. Sekhon’s case the police officer’s evidence about “blind couriers” effectively enabled the officer to give an opinion on whether Mr. Sekhon knew he was carrying drugs. That question was central to the determination of the guilt or innocence of Mr. Sekhon. And, that opinion was based on the officer’s opinion about the guilt or innocence of other accused persons in past investigations. That was something which was clearly outside the permissible scope of expert opinion evidence.  The Supreme Court of Canada was right to say so.