R v Lacasse, [2015] S.C.J. No.64 (Wagner):

[113] In the instant case, the driving prohibition has the same effect regardless of whether it was imposed before or after the respondent was sentenced. In R. v. Sharma, [1992] 1 S.C.R. 814, Lamer C.J., dissenting, explained that the accused had in fact begun serving his sentence, given that the driving prohibition would have been imposed as part of his sentence had he been tried and found guilty within a reasonable time. In short, where a driving prohibition is not only one of the release conditions imposed on an accused but also part of the sentence imposed upon his or her conviction, the length of the presentence driving prohibition must be subtracted from the prohibition imposed in the context of the sentence.

[114] In my view, therefore, the driving prohibition of four years and seven months imposed in this case is demonstrably unfit and must be reduced to two years and four months to take account of the recognizance entered into by the respondent under which he was to refrain from driving from his release date until his sentencing date (two years and three months).