Detective Douglas Backus

The appellant, Nicholas Wong, appealed his dangerous offender designation and indeterminate sentence.

He was convicted of two counts of attempted murder with a firearm and other related offences.

The Crown sought the dangerous offender designation based on a pattern of repetitive and persistent aggressive behaviour, including prior firearm possession offences.

Wong argued the sentencing judge erred by considering firearm possession as part of the pattern and by admitting expert evidence on gang affiliation and prior gun use.

The Court of Appeal dismissed the appeal, finding no errors in the sentencing judge's determination that Wong met the dangerous offender criteria, nor in the admission of the challenged evidence.

The Crown applied to call a police detective as an expert witness on street gangs in a first-degree murder trial.

The accused opposed the application, arguing the expert was biased and the proposed evidence, including rap videos, letters, and graffiti, was highly prejudicial.

The court found the expert evidence necessary and the detective qualified.

The court admitted most of the videos, letters, and graffiti, finding their probative value in establishing motive and the existence of a criminal organization outweighed their prejudicial effect, but excluded evidence of the accused's prior convictions and certain letters.

The accused, Jermaine Gager, brought an application for a mistrial during his joint trial for first-degree murder with co-accused Corey Smelie.

The application was based on the closing address of counsel for the co-accused, who improperly commented on his client's failure to testify and suggested he was afraid of retribution from the moving party.

The court found the remarks were improper but concluded that the resulting prejudice was not irremediable.

The court dismissed the mistrial application, holding that a specific curative instruction to the jury would be sufficient to ensure trial fairness.

In a first degree murder prosecution involving alleged gang rivalry, the accused applied to qualify a sociologist as an expert witness on street gangs.

The Crown opposed the qualification, arguing that the proposed expert lacked sufficient knowledge of the specific Toronto gangs at issue and that aspects of his methodology and impartiality were problematic.

The court conducted the two‑stage admissibility analysis for expert evidence under Mohan and Abbey, expressing significant concerns about the expert’s methodology, potential bias, inflated data samples, and limited familiarity with Toronto gangs.

Despite these reservations, the court held that the threshold for excluding defence expert evidence was not met and qualified the witness as an expert in limited areas relating to gang culture and behaviour.

The court then set detailed restrictions on the permissible scope of the expert’s testimony, particularly preventing opinions that would approach the ultimate issue of gang membership.

In a first-degree murder trial involving alleged street gang members, the Crown applied to qualify a police detective as an expert on Toronto street gangs.

The defence brought parallel applications seeking further disclosure of police records, including confidential informant databases, debriefing notes, training presentations, and wiretap intercepts from other investigations.

The court ordered redacted disclosure of the debriefing notes and presentations but denied access to the informant database and the massive wiretap files, finding the latter to be third-party records that did not meet the threshold for likely relevance.

The court qualified the detective as an expert but strictly limited the scope of his permissible opinion evidence to prevent him from usurping the jury's fact-finding function, particularly regarding whether specific individuals were gang members or whether a 'gang war' existed.