The length of a probation term is still not something that should be decided lightly. Sometimes, but I will say, not that frequently, a prosecutor will demand the term of probation be for the maximum period and defence counsel do not complain about the proposed term. However, unless there is rehabilitative purpose to the length of the term, the length of term should not be longer for a purpose other than for rehabilitation. This principle may be drawn from the case of R. v. Ziatas (1973), 13 C.C.C. (2d) 287 (Ont. C.A.). The point was a little different as it concerned a probation condition not the length of the term. There, the condition not to drive a vehicle was considered purely punitive, not rehabilitative. However, by the same principle, the length of the term should be based on consideration that are not strictly punitive.
Today, the Court of Appeal for Ontario in R. v. Blais, 2011 ONCA 133 (CanLII) 2011-02-16, made this statement that actually is helpful in instances where the prosecution seeks a lengthy probation term, in the absense of a significant criminal history:
 In the light of the appellant’s extensive record, and the rehabilitative objective of a probation order, a three-year term is appropriate. At the sentencing hearing, the appellant expressed his intent to turn his life around. We view the probation order as promoting his ability to do so.