Ontario Court Of Appeal Affirms Trial Judges As 'Robust Gatekeepers' Of Expert Evidence

In the face of the trend in litigation towards an ever greater reliance on expert evidence, the recent Ontario Court of Appeal decision in Meady v Greyhound Canada Transportation Corp. 2015 ONCA 6 ("Meady") upholding a trial judge's decision to exclude the evidence of two of the plaintiffs' expert witnesses on the grounds that their evidence was not necessary, signals to litigants and lower courts alike the expectation that trial judges will act as robust gatekeepers to control the admission of expert evidence, and that their decisions to exclude expert evidence will be given deference.

Background

In December of 2000, Shaun Davis, a 21-year-old passenger of a Greyhound bus driving through Northern Ontario, left his seat and grabbed the steering wheel from the bus driver, causing the bus to veer off the road and topple on its side, killing one passenger and injuring many others.

Mr. Davis suffered from paranoid delusions, and prior to boarding the bus had interacted with two OPP officers who found him to be displaying signs of anxiety and paranoia but who nonetheless concluded that he did not pose a threat to anyone. The police officers told the bus driver about Mr. Davis' paranoia; however, the driver allowed Mr. Davis to board the bus, and let him sit up front.

After the accident, a number of the passengers commenced an action naming Greyhound, the bus driver, the two OPP officers and the OPP.

The matter went to trial in 2010, and after 65 days of evidence from 83 witnesses, Justice Platana dismissed the action against all of the defendants except Davis.

The plaintiffs appealed.

At issue on the appeal was the decision by Justice Platana at trial to exclude the evidence of two expert witnesses tendered by the plaintiffs: a retired police officer who opined that the OPP officers had failed to meet the standard of care of reasonable and prudent officers by failing to detain Mr. Davis under the Mental Health Act or the common law doctrine of investigative detention; and a transportation safety consultant who had experience as an accident investigator and in drafting policies and standards for training bus drivers who opined that the bus driver was negligent in his operation of the bus.

Exclusion of Expert Evidence at Trial

At trial, Justice Platana excluded the evidence of the retired police officer on the basis that while expert evidence concerning the standard of care of professionals such as police officers may be required in some cases, it...