The principle of restraint has been derived from the interpretation of s. 718.2(d) and (e).
Section 718.2 states:
- (d) an offender should not be deprived of liberty, if less restrictive sanctions may be appropriate in the circumstances; and
- (e) all available sanctions other than imprisonment that are reasonable in the circumstances should be considered for all offenders, with particular attention to the circumstances of aboriginal offenders.
1995, c. 22, s. 6; 1997, c. 23, s. 17; 2000, c. 12, s. 95; 2001, c. 32, s. 44(F), c. 41, s. 20; 2005, c. 32, s. 25; 2012, c. 29, s. 2; 2015, c. 13, s. 24, c. 23, s. 16.
Restraint is an important principle that should be "used in an appropriately reasonable but humane manner". It should "invigorat[e] the confidence of the public that sentences imposed are both just and fair". 
For first time offenders, the principle of restraint "requires that the sentencing judge consider all sanctions apart from incarceration" and where necessary ensure the term be as "short as possible and tailored to the circumstances of the accused".
The principle also requires the judge to consider rehabilitation in setting the length of the sentence. 
"General deterrence cannot be the sole consideration. Appropriate consideration must be given to the rehabilitation of the offender."
Parliament codified the principle of restraint in order to limit the use of incarceration.
Restraint not only means that prison should be a sanction of last resort, but also means that the court should "seek the least intrusive sentence and the least quantum which will achieve the overall purpose of being an appropriate and just sanction."
Where other dispositions have been tried and failed, and jail has not previously been imposed, the imposition of a "short, sharp" sentence can be appropriate, particularly where the offence is related to property and not violence.
Where mental health issues played a central role in the commission of the offence, deterrence and punishment are of less importance.
R v MacDonald (1997), 113 CCC (3d) 418 at para 147 per Lane JA ("I read s. 718.2(d) and (e) as a clear intention on the part of Parliament to reduce
institutional incarceration and to adopt the principle of restraint.")
R v Gladue,  1 SCR 688, 1999 CanLII 679 (SCC) at paras 37 to 41
- R v May, 2012 ABCA 213 (CanLII)
R v Battise 2009 ONCA 114 (CanLII) at para 32
R v Priest 1996 CanLII 1381 (ONCA) 30 OR (3d) 538 at p. 545
R v Batisse, 2009 ONCA 114 (CanLII), at para 32
Batisse, supra at para 33
- R v Blanas, 2006 CanLII 2610 (ON CA), (2006), 207 O.A.C. 226, at para 5
- Batisse, supra at para 35
- R v Hamilton 2004 CanLII 5549 (ON CA) at para 96
- R v Vandale (1974), 21 CCC (2d) 250, per Martin JA citing McKenna J. of the English Court of Appeal in R v Curran (1973), 57 Crim. App. R. 945 ("As a general rule it is undesirable that a first sentence of immediate imprisonment should be very long, disproportionate to the gravity of the offence and imposed as this sentence was for reasons of general deterrence, that is, as a warning to others.")
- Batisse, supra at para 38
Where a first-time offender is to be sentenced a judge should consider all possible dispositions other than incarceration. Custody should only be imposed where "the offence is of such gravity that no other sentence is appropriate". It is preferable in most cases that non-violent first time offenders be punished in other ways than incarceration.
R v Stein (1974), 15 CCC (2d) 376, at para 4 per Martin JA ("In our view, before imposing a custodial sentence upon a first offender the sentencing Court should explore the other dispositions which are open to him and only impose a custodial sentence where the circumstances are such, or the offence is of such gravity that no other sentence is appropriate")
R v Priest,  30 O.R. (3d) 538, at para. 20 per Rosenberg JA ("The duty to explore other dispositions for a first offender before imposing a custodial sentence is not an empty formalism which can be avoided merely by invoking the objective of general deterrence. It should be clear from the record of the proceedings, preferably in the trial judge’s reasons, why the circumstances of this particular case require that this first ") R. v. Pierce, 1996 CanLII 1381 (ON CA),  30 O.R. (3rd) 538 (Ont. C.A.) - courts should consider non-custodial sentences in appropriate cases of first time offenders
R v Laschalt, (1993), 81 C.C.C. (3d) 154 at p. 59 per Sinclair JA ("The imprisonment of non-violent first offenders is counter-productive. It strains a system already strained by more violence and repeat offenders than it can rehabilitate. It often results in a first offender emerging bitter and more ready to commit further crimes. Better that a non-violent, first offender be punished in another way")