Judge in judge alone trial has jurisdiction to reverse a finding of guilt suo sponte

R. v. Griffith, 2013 ONCA 510 holds:

[12]       On the basis of this court's decision in R. v. Lessard (1977), 30 C.C.C. (2d) 70, it cannot be doubted that the trial judge was not functus until he imposed sentence. In Lessard, Martin J.A., speaking for the court, held that a judge sitting without a jury is not functus officio until he has imposed sentence or otherwise finally disposed of the case. Therefore, a judge who has made a finding of guilt, either as a result of a guilty plea or on disputed facts, is empowered to vacate the adjudication of guilt at any time before a sentence is imposed. In Lessard, the court held that the trial judge had the power to grant an application by the accused to reopen his case after a finding of guilt so that he could adduce further evidence. But, at p. 73, Martin J.A. stressed that the power to vacate the adjudication of guilt after a trial "should only be exercised in exceptional circumstances and where its exercise is clearly called for".

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[16]       I would not give effect to this submission. While I accept that the power to reopen is to be exercised only in exceptional circumstances, there is nothing inLessard, or in the cases referred to in Lessard, that would limit the power to an application by one of the parties. Rather, at p. 73 of Lessard, Martin J.A. referred to S. (An Infant) v. Recorder of Manchester, [1970] 2 W.L.R. 21, and founded the power to reopen on the duty of the court to clear the innocent – a duty "equal or superior in importance to its duty to convict and punish the guilty".

[17]       To take one clear example, if the law under which the accused was convicted was held to be unconstitutional between conviction and sentence, it would be open to the judge to reopen the case and vacate the conviction, even if there had been no application by the accused or the Crown. Although, as I will explain below, the proper remedy in this case was to declare a mistrial and not enter an acquittal, the absence of a statutory basis does not deprive a trial judge of the power to reopen the case: see Re Regina and Bertucci (1984), 11 C.C.C. (3d) 83 (Sask. C.A.), at p. 88.