Restitution (Specific) - Against Government. Professional Institute of the Public Service of Canada v. Canada (Attorney General)
In Professional Institute of the Public Service of Canada v. Canada (Attorney General) (SCC, 2020) the Supreme Court of Canada considered whether restitution can apply against government [it could], and that enrichment can take the form of 'relief from a negative' [it can]:
(2) Unjust Enrichment
 As this Court found in Elder Advocates, it is possible to claim unjust enrichment against the government (provided the issue is not restitution for taxes paid under an ultra vires statute).
 In order to prove a claim in unjust enrichment, the plaintiff must establish: (1) an enrichment of the defendant; (2) a corresponding deprivation of the plaintiff; and (3) an absence of juristic reason for the enrichment (Pacific National Investments Ltd. v. Victoria (City), 2004 SCC 75,  3 S.C.R. 575 (“Pacific National”), at para. 14). Where these elements are satisfied, the remedy of constructive trust may be available if (1) “monetary damages are inadequate”, and (2) “there is a link between the contribution that founds the action and the property in which the constructive trust is claimed” (Peter v. Beblow, 1993 CanLII 126 (SCC),  1 S.C.R. 980, at p. 988).
 As Binnie J. explained in Pacific National, at para. 15, “[a]n enrichment may ‘connot[e] a tangible benefit’ . . ., or it can be relief from a ‘negative’, such as saving the defendant from an expense he or she would otherwise have been required to make” (emphasis in original).
 Following this Court’s decision in Peter v. Beblow, the enrichment must correspond with a deprivation from the plaintiff. While the test for unjust enrichment is typically articulated as having three elements, it is important to recognize that the enrichment and detriment elements are the same thing from different perspectives. As Dickson C.J. suggested in Sorochan v. Sorochan, 1986 CanLII 23 (SCC),  2 S.C.R. 38, cited by Cory J. in his concurring reasons in Peter v. Beblow, at p. 1012, the enrichment and the detriment are “essentially two sides of the same coin”.
 The “straightforward economic approach”, as described in Pacific National, to enrichment and detriment, is properly understood to connote a transfer of wealth from the plaintiff to the defendant (para. 20). As the purpose of the doctrine is to reverse unjust transfers, it must first be determined whether wealth has moved from the plaintiff to the defendant.
 Accordingly, the first inquiry is not whether the government was somehow enriched or benefitted by amortizing or removing the surpluses in the Superannuation Accounts. Rather, the question is whether the government was enriched at the appellants’ expense. Even if it could be shown that the government benefited in some way by reducing the stated financial obligations of Canada, it would not assist the appellants unless the gain corresponded to the appellants’ loss.
 As the Superannuation Accounts are mere accounting records, and do not contain assets in which the appellants have an interest, no enrichment and corresponding deprivation can be found in either (1) the government’s decision prior to April 1, 2000 to amortize the surpluses for accounting purposes under the FAA, or (2) Parliament’s decision to enact Bill C-78 to require the debiting of a portion of the surplus directly from the Accounts.
 The Court of Appeal found that there was no enrichment because “whatever benefit there was to such actions enured to all Canadian taxpayers” (para. 106). I do not understand the nature of the inquiry in the same way. The enrichment and corresponding deprivation elements ask whether there was a transfer of wealth from the plaintiff to the defendant. The fact that the defendant is a public body is irrelevant to whether such a transfer of wealth took place. Indeed, this reasoning would have the effect of insulating the government from any claim for unjust enrichment.
 The Court of Appeal indicated that there might have been a deprivation because the government’s actions “were detrimental to plan members if for no other reason than the fact that those actions apparently led to increases in plan member contribution rates” (para. 107). As I observed in connection with the issue of whether the Superannuation Accounts contained assets, the evidence does not support such an alleged deprivation.
 Further, if the increase in contribution rates did constitute a deprivation, the corresponding enrichment could only be the additional deductions taken from employee pay cheques following the rate hikes, and not the amount of the surpluses amortized and removed. But the appellants have sought a declaration that they have an equitable interest in the balances in the Superannuation Accounts as at March 31, 2000, and not the return of the increased contributions after Bill C-78 came into force. Accordingly, on the argument that increased contribution rates constituted a deprivation, there is no link between the alleged deprivation and the property right they seek, the return of the amortized surplus and subsequently debited surplus.
 I conclude that there was no enrichment and corresponding deprivation, and that the appellants have not established a prima facie case of unjust enrichment. The third branch of the test for unjust enrichment, the absence of a juristic reason for the enrichment, need not be analyzed.