“There is no dispute that courts generally have the power to award retroactive child and spousal support where warranted. Although the two claims are distinct, the considerations and criteria underlying both awards, and the arguments relating to them, overlap. That said, there remain differences in the approaches to them. Relying on the analysis of Bastarache J. in D.B.S. v. S.G.R., 2006 SCC 37, [2006] 2 S.C.R. 231, (a retroactive child support case), Cromwell J. summarized this in Kerr v. Baranow, 2011 SCC 10, [2010] 1 S.C.R. 369, (a retroactive spousal support case), at paras. 206-7 in the following way:
… I prefer to follow the example of Bastarache J. in [D.B.S.] and consider the relevant factors that come into play where support is sought in relation to a period predating the order.
While [D.B.S] was concerned with child as opposed to spousal support, I agree … that similar considerations to those set out in the context of child support are also relevant to deciding the suitability of a “retroactive” award of spousal support. Specifically, these factors are the needs of the recipient, the conduct of the payor, the reasons for the delay in seeking support and any hardship the retroactive award may occasion on the payor spouse. However, in spousal support cases, these factors must be considered and weighed in light of the different legal principles and objectives that underpin spousal as compared with child support. I will mention some of those differences briefly, although certainly not exhaustively.
The primary difference highlighted by Cromwell J. relates to the different legal foundations upon which child and spousal support are based. Child support is automatic; spousal support is not. Cromwell J. articulated this at para. 208:
Spousal support has a different legal foundation than child support. A parent-child relationship is a fiduciary relationship of presumed dependency and the obligation of both parents to support the child arises at birth. In that sense, the entitlement to child support is “automatic” and both parents must put their child’s interests ahead of their own in negotiating and litigating child support. Child support is the right of the child, not of the parent seeking support on the child’s behalf, and the basic amount of child support under the Divorce Act, R.S.C. 1985, c. 3 (2nd Supp.), (as well as many provincial child support statutes) now depends on the income of the payor and not on a highly discretionary balancing of means and needs. These aspects of child support reduce somewhat the strength of concerns about lack of notice and lack of diligence in seeking child support. With respect to notice, the payor parent is or should be aware of the obligation to provide support commensurate with his or her income. As for delay, the right to support is the child’s and therefore it is the child’s, not the other parent’s position that is prejudiced by lack of diligence on the part of the parent seeking child support: see [D.B.S.], at paras. 36-39 ,47-48, 59, 80 and 100-104. In contrast, there is no presumptive entitlement to spousal support and, unlike child support, the spouse is in general not under any legal obligation to look out for the separated spouse’s legal interest. Thus, concerns about notice, delay and misconduct generally carry more weight in relation to claims for spousal support. [Emphasis added.]
In the context of dealing with both retroactive spousal and retroactive child support claims, Kerr and D.B.S. both emphasize, in the end, “the need for flexibility and a holistic view of each matter on its own merits”: Kerr, at para. 212; D.B.S., at para. 99.”