When a client is being sentenced, it is the duty of a criminal defence lawyer to put forth to the Court all the relevant and important mitigating circumstances of the case in an effort to reduce the sentence as much as possible. Mitigating circumstances can arise from many facets of the case including the accuseds life (eg. In a case of theft, the accused was addicted to gambling.), from within the offence itself (eg. In a case of assault, for example, no injuries were inflicted upon the victim.), from the accuseds behaviour post-arrest (eg. The accused confessed upon arrest.), and from the impact of the process of the criminal justice system upon the accused (eg. The accused was denied bail and spent time in jail while awaiting trial.).
It is well-established law that where an accused has been denied bail or spent time in jail before being granted bail, he should be given credit for pre-sentence custody. Section 719(3) of the Criminal Code of Canada allows a Court to take into account any time spent in custody by the accused as a result of the offence. While there is no fixed formula, the Courts have generally stated that a sentencing court should give more than one-for-one credit for pre-sentence custody in recognition of the circumstances that usually attend pre-sentence custody. In fact, Courts will typically give two-for-one credit for pre-sentence custody and, in some instances, enhance the credit even further where the circumstances under which the accused was detained have been particularly difficult, such as where there is an overcrowding in the jail and people are crammed into cells together.
On the flipside, in some instances, Courts have given less than two-for-one because of the circumstances of the custody or the reasons for the detention.
But what about difficult bail conditions? Can an onerous bail be considered as a mitigating factor? Making this argument is far more difficult than the arguing for mitigation for pre-trial custody. Unlike pre-trial custody, there is no statutory provision within the Criminal Code that addresses this issue. Secondly, even stringent bail conditions such as house arrest often allow the accused exceptions for work, schooling, medical appointments, and so on. Thirdly the impact of bail conditions on the accused is not usually obvious unlike pre-trial custody where the loss of liberty is quite apparent.
However, it can be argued that an accused person who has been under stringent bail conditions for a prolonged period of time has had his liberty infringed and suffered a form of punishment already that should be taken into consideration. In fact, the Ontario Court of Appeal in the case of R. v. Downes  79 O.R. (3d) 321 has stated, that time spent under stringent bail conditions, especially under house arrest, must be taken into account as a relevant mitigating circumstance. However, like any potential mitigating circumstance, there will be variations in its potential impact on the sentence and the circumstances may dictate that little or not credit should be given for pre-sentence house arrest. The Court went on to state that the amount of potential credit will depend upon a number of factors including, the length of time spent on bail under house arrest; the stringency of the conditions; the impact on the offenders liberty; the ability of the offender to carry on normal relationships, employment and activity. The onus will be on the offender on a balance of probabilities to establish the negative impact of the bail conditions.