TORONTO -- Some of the people found guilty by juries in Ontario in recent months are quickly taking steps to challenge their convictions in light of a new ruling on jury selection by the province's top court.

One of two men convicted in a high-profile sexual assault trial in Toronto filed a notice of appeal on Thursday, referencing the Court of Appeal for Ontario ruling released that same day.

Gavin MacMillan is seeking to have his conviction overturned on grounds the trial judge erred in denying him the right to use peremptory challenges during jury selection.

The federal government eliminated the use of peremptory challenges, a mechanism through which lawyers on either side can veto a certain number of prospective jurors without explanation, as part of major legal reforms that took effect on Sept. 19 of last year.

In a unanimous decision issued Thursday, the appeal court said the new rule should not be applied to cases already in the system in which the accused requested a trial by jury before the law came into force.

Legal experts have said the ruling could affect dozens of cases heard by juries in Ontario since the changes took effect.