Federal Court Upholds Res Judicata in Disability Benefits Case

Date: 20260526 Docket: T-984-24 Citation: 2026 FC 672 Ottawa, Ontario, May 26, 2026 PRESENT: The Honourable Mr. Justice Southcott BETWEEN: [NAME] Applicant and ATTORNEY GENERAL OF CANADA Respondent

REASONS AND

JUDGMENT I. Overview [ 1 ] This is an application for judicial review of a decision of the Social Security Tribunal of Canada [[NAME]], Appeal Division [Appeal Division] dated January 30, 2024 [the AD Decision]. [ 2 ] In the AD Decision, the Appeal Division refused to grant the Applicant leave to appeal the decision of the General Division of the [NAME] [General Division] dated November 28, 2023 [the GD Decision]. The General Division had concluded that that the Applicant’s effort to revisit her eligibility for [NAME] [[NAME]] disability benefits, following a 2008 decision of the Review Tribunal (the predecessor to the General Division) finding her ineligible, was barred by the principle of res judicata . [ 3 ] As explained in greater detail below, this application is dismissed, because the AD Decision is reasonable.

II. Background [ 4 ] The Applicant applied for a [NAME] disability pension in 2005 following two workplace accidents that occurred during the performance of her duties as a health care aide. [ 5 ] The relevant Minister refused the application, and the Applicant appealed to the Review Tribunal, which held a hearing on April 15, 2008. In a decision dated June 2, 2008, the Review Tribunal dismissed the appeal because the evidence did not demonstrate that the Applicant had a severe and prolonged disability by the date she last qualified for a [NAME] disability pension. The Applicant did not appeal that decision. [ 6 ] In April 2022, the Applicant submitted a fresh application for [NAME] disability benefits on the same basis as her previous Application. The Minister refused the new application on the basis that the Review Tribunal’s decision was final as to the Applicant’s eligibility for [NAME] disability benefits. [ 7 ] The Applicant appealed the Minister’s decision to the General Division, which held a hearing on November 16, 2023. In the subsequent GD Decision, the General Division dismissed the Applicant’s appeal, concluding that the principle of res judicata applied, because the issues and parties in both appeals were the same and the Review Tribunal’s decision was final. The General Division also held that there was no injustice in deciding not to hear the appeal, as the hearing before the Review Tribunal was procedurally fair, the Review Tribunal had considered the Applicant’s medical issues and the evidence related thereto, and the purpose, process and stakes in both appeals were the same. [ 8 ] The Applicant applied for leave to appeal to the Appeal Division, arguing that the General Division had erred by not considering recent medical reports. [ 9 ] On January 30, 2024, the Appeal Division issued the AD Decision that is the subject of this application for judicial review.

III. Decision under Review [ 10 ] The Appeal Division dismissed the application for leave to appeal, finding that the Applicant failed to raise an arguable case of the sort required by paragraphs 58.1(a) and (b) of the Department of Employment and Social Development Act , SC 2005, c 34 [DESDA], and (considering paragraph 58.1(c) of DESDA) failed to set out evidence not presented to the General Division that would justify granting permission to appeal. [ 11 ] The Appeal Division concluded that there was no arguable case that the General Division made an error of fact by ignoring the Applicant’s medical evidence, especially recent medical reports that included an X-ray and MRI results. The Appeal Division identified that the General Division had discussed an imaging report from August 2021 and an MRI from August 2023 and had concluded that this evidence did support a conclusion that the 2008 hearing at the Review Tribunal was unfair. The Appeal Division explained that the General Division did not ignore these reports. Rather, the reports did not change the outcome of the General Division’s application of the principle of res judicata , which precluded the hearing of a matter that had already been heard. [ 12 ] The Appeal Division also noted that, after the General Division hearing, the Applicant submitted additional medical documents on November 19, 2024, and the General Division explained to the Applicant that it would not consider the late evidence because it was not relevant to the issue of res judicata . The Appeal Division concluded that refusing to consider these late reports, because they were not relevant to the issue the General Division was required to address, was different from making an error of fact by ignoring them. [ 13 ] Additionally, the Appeal Division identified that the Applicant had attached medical documents to her application for leave to appeal, the majority of which had been presented to the General Division. The Appeal Division noted that the new evidence was an MRI report of the Applicant’s right shoulder from 2022 but concluded that this document was not relevant to the issue of whether the General Division may have made an error in its application of the res judicata principle. [ 14 ] In conclusion, the Appeal Division explained that it was satisfied that the General Division did not ignore or misunderstand the evidence when it decided not to hear the same issue that the Review Tribunal had already decided. The Appeal Division found that the General Division had considered and applied the available evidence to the law surrounding the principle of res judicata , including considering in detail whether applying that principle would result in injustice.

IV. Law [ 15 ] [NAME] 58.1 of the DESDA sets out as follows the relevant jurisdiction of the Appeal Division to grant leave to appeal: Leave to appeal — Income Security [NAME] 58.1 Leave to appeal a decision made by the Income Security [NAME] is to be granted if the application for leave to appeal (a) raises an arguable case that the [NAME] failed to observe a principle of natural justice or otherwise acted beyond or refused to exercise its jurisdiction; (b) raises an arguable case that the [NAME] erred in law, in fact or in mixed law and fact, in making its decision; or (c) sets out evidence that was not presented to the [NAME]. Permission d’en appeler — [NAME] de la sécurité du revenue 58.1 La demande de permission d’en appeler d’une décision rendue par la [NAME] de la sécurité du revenu est accordée dans les cas suivants : a) la demande soulève une cause défendable selon laquelle la [NAME] n’a pas observé un principe de justice naturelle ou a autrement excédé ou refusé d’exercer sa compétence; b) elle soulève une cause défendable selon laquelle la [NAME] a rendu une décision entachée d’une erreur de droit, de fait ou de droit et de fait; c) elle présente des éléments de preuve qui n’ont pas été présentés à la [NAME].

V. Issues [ 16 ] The Applicant’s Memorandum of Fact and Law advances arguments to the effect that the General Division, and subsequently the Appeal Division, failed to properly apply (and intelligibly explain the application of) the principle of res judicata , including the discretion not to apply the principle if it would result in an injustice. In considering those arguments, the issue that the Court must address in this application for judicial review is whether the AD Decision is reasonable. [ 17 ] Consistent with that articulation, the Court’s review of the AD Decision is governed by the standard of reasonableness ( [NAME] v Canada (Attorney General) , 2023 FC 102 at paras 20-21, aff'd 2024 FCA 102, leave to appeal to SCC denied, 41441 (13 February 2025); Canada (Minister of Citizenship and Immigration) v [NAME], 2019 SCC 65 [ [NAME] ] at paras 16-17). [ 18 ] A further preliminary issue developed on the day of the hearing of this application, in that the Applicant sought to add to the record before the Court a medical report dated April 28, 2026, from [NAME] [the 2026 Medical Report]. The Respondent took the position that the 2026 Medical Report is inadmissible, because it was not before the Appeal Division when it made the AD Decision. The parties presented argument on this issue at the hearing, and the Court reserved its decision on the admissibility of this document. I will accordingly address this issue in these Reasons.

VI. Analysis A. Admissibility of 2026 Medical Report [ 19 ] In the 2026 Medical Report, [NAME] describes the Applicant having been seen in 2007 for right shoulder pain as a result of a work-related injury in 2004, which prevented her from working between 2004 and 2007, and notes that the Applicant was then referred to an orthopedic surgeon. [ 20 ] In support of its position that the Court should not admit the 2026 Medical Report, the Respondent notes that, in reviewing the reasonableness of an administrative decision (and subject to exceptions that do not apply in the matter at hand), a court will typically consider only the evidence that was before the administrative decision-maker when the decision was made ( Association of Universities and Colleges of Canada v [NAME] (Access Copyright) , 2012 FCA 22 [ Access Copyright ] at paras 19-20). [ 21 ] The Applicant argues that the Court should admit this evidence, because it represents further support for the medical evidence that is already in the record before the Court. However, it is clear from its date, which significantly postdates the AD Decision, that the 2026 Medical Report was not itself before the Appeal Division when it made the decision under review in this application. Applying the principles underlying Access Copyright , it would not be appropriate for the Court to take into account, in reviewing the AD Decision for reasonableness, evidence of which the Appeal Division did not have the benefit when the decision was made. As such, while my Judgment will provide for the 2026 Medical Report to be placed on the Court file, it will not be admitted into evidence in this application. B. Reasonableness of Decision [ 22 ] As previously noted, the Applicant argues that the General Division, and subsequently the Appeal Division, failed to properly apply (and intelligibly explain the application of) the principle of res judicata , including the discretion not to apply the principle if it would result in an injustice. The Applicant submits that the AD Decision is therefore unreasonable. These arguments are based on the principle, explained at paragraph 86 of [NAME] , that reasonable administrative decision-making requires that the decision-maker intelligibly articulate the reasons for the Decision. [ 23 ] Both the GD Decision and the AD Decision turned on the application of the doctrine of res judicata , which the Supreme Court of Canada has described as promoting finality in litigation and precluding re-litigation of an issue that has already been decided ( [NAME] v [COMPANY] , 2001 SCC 44 [ [NAME] ] at para 18). [NAME] (at paras 54 to 59), the Respondent describes this doctrine as applying (in the context of an appeal such as in the matter at hand) when three requirements are met: (a) the issue in the current appeal is the same as the issue in an earlier appeal; (b) the parties are the same in both appeals; and (c) the decision in the earlier appeal was final. [ 24 ] The Applicant has not raised any disagreement with these descriptions or argued that the three requirements described above have not been met. Rather, the parties’ disagreement turns on the application of a second step in a res judicata analysis, which (again in the context of an appellate administrative tribunal) affords the tribunal a discretion to hear an appeal if it would be unjust not to do so ( [NAME] at para 62-67). [ 25 ] In [NAME] v [NAME] (Regional Police Services Board) , 2013 SCC 19 [ [NAME] ] at paragraph 38, the Supreme Court referenced a list of factors identified in [NAME] as indicating circumstances that in a particular case may be relevant to the exercise of the relevant discretion. [NAME] emphasized that there is no set list of factors to consider as to whether it would be unjust or unfair to apply res judicata but explained that, broadly speaking, the factors identified in the jurisprudence illustrate that unfairness may arise in two main ways: (a) unfairness in the conduct of the prior proceeding; or (b) even where the prior proceeding was conducted fairly, where it may nonetheless be unfair to use the results of that proceeding to preclude a subsequent proceeding, for example where there is a significant difference between the purposes, processes or stakes involved in the two proceedings (at paras 38-39, 42). [ 26 ] Against that jurisprudential backdrop, the Applicant argues that, while the General Division acknowledged the existence of the injustice exception, it resolved the injustice inquiry through conclusory reasoning, failing to engage with the Applicant’s submissions regarding fairness, her self-representation in the earlier proceedings, or the passage of time. The Applicant emphasized at the hearing of this application for judicial review that the injustice inquiry is not limited to considering whether the earlier proceeding was procedurally unfair. Her oral submissions before the Court referenced elements of her medical history and related documentation as supporting a conclusion that the Review Tribunal had made errors in its 2008 decision, that she met the requirements for [NAME] disability benefits at that time, and that her disability has persisted. [ 27 ] Similarly, the Applicant submits that the Appeal Division addressed the injustice inquiry through conclusory reasoning, stating only that the General Division had considered in detail whether applying the rule against deciding something that has already been decided would result in an injustice. The Applicant argues that that this reasoning does not withstand the review for intelligibility demanded by [NAME] . [ 28 ] The Respondent argues that the AD Decision is justified, intelligible and transparent, as the Appeal Division did what it was required to do: it considered the Applicant’s arguments and made findings about whether they had a reasonable chance of success on appeal. The Respondent submits that the Appeal Division reasonably found that the Applicant’s arguments and new evidence that she adduced did not support a conclusion that the General Division erred when dismissing her appeal due to the application of the doctrine of res judicata . [ 29 ] In the case at hand, it is the Appeal Division’s decision that is under review. My analysis will therefore focus upon that decision, although the reasons provided by the General Division in the GD Decision of course remain germane, as the Appeal Division was required to consider whether the Applicant had raised a ground of appeal of the GD Decision that had a reasonable chance of success. [ 30 ] In considering the parties’ respective positions, it is important for the Court to take into account the particular arguments that the Applicant advanced before the Appeal Division. These are found in the document entitled “Application to the Appeal Division - Income Security” , signed by the Applicant on January 25, 2024 [the Leave Application]. The Applicant ticked boxes, indicating “I think there is an arguable case that the General Division made a mistake in deciding the appeal” and “I have evidence that the General Division didn’t have” and added the following detail: The General Division did not take into consideration my recent medical reports i.e. x-rays & MRI. I have unresolved pain to this day that was caused & has progressively gotten worse because of the work place injury I endured. My prolonged disability began in 2004, and has been observed by my physicians who have expressed their concerns. Please find attached medical evidence. [ 31 ] Consistent with the Appeal Division’s jurisdiction under [NAME] 58.1 of the DESDA and the contents of the Leave Application, the AD Decision identifies two issues in the appeal: (a) whether the Applicant raised an arguable case that the General Division made an error of fact by ignoring her medical evidence; and (b) whether the Leave Application set out evidence that was not presented to the General Division. Consistent with the basis for the General Division’s rejection of the Applicant’s appeal to it, which turned on the doctrine of res judicata , the Appeal Division addressed both issues in the context of the General Division’s reliance on that doctrine. [ 32 ] In relation to the issue surrounding an error of fact, the Appeal Division noted the Applicant’s argument that the General Division had made such an error by ignoring her medical evidence, in particular an x-ray and MRI results, as well as the Applicant’s explanation that she had unresolved pain caused by workplace injury that has worsened over time. However, noting that the General Division discussed both an August 2021 imaging report and an August 2023 MRI, the Appeal Division found that the General Division had not ignored these reports. Rather, the General Division found that these reports did not assist the Applicant in demonstrating that the 2008 hearing before the Review Tribunal was unfair so as to avoid the application of res judicata . [ 33 ] Similarly, the Appeal Division referenced the medical documents that the Applicant provided to the General Division after the hearing. The Appeal Division found no error by the General Division in rejecting the late evidence as irrelevant to considering whether to apply the res judicata doctrine. Again, the Appeal Division found that refusing to consider the late reports on this basis was different from making an error of fact by ignoring them. [ 34 ] I appreciate that this reasoning does not include the Appeal Division conducting its own detailed analysis of the application of the res judicata doctrine (including the injustice exception). Rather, the Appeal Division explained its finding that the General Division had not failed to account for that evidence. The General Division considered the evidence and concluded that it did not affect the res judicata analysis (which analysis by the General Division, as noted later in the AD Decision, included the injustice exception). It is important to recognize that the Leave Application did not advance arguments of the sort raised in this application for judicial review, to the effect that the General Division erred in its application of the injustice exception to res judicata doctrine. The analysis in the AD Decision is responsive to the Applicant’s submissions in the Leave Application, which argued that the General Division had erred by failing to take her medical evidence into consideration. That analysis by the Appeal Division is intelligible, and I find that it withstands reasonableness review. [ 35 ] The Appeal Decision then considered the issue whether the Applicant had adduced new evidence in her Leave Application, not presented to the General Division, that would justify granting permission to appeal. The Appeal Division identified one document that had not already been presented to the General Division (an MRI report of the Applicant’s right shoulder from 2022 [2022 MRI Report]) and considered the relevance of that evidence to whether the General Division had made an error in applying the res judicata doctrine. [ 36 ] In concluding that there was no such error, the Appeal Division noted that the Review Tribunal had decided in 2008 that the Applicant’s disability was not severe within the meaning of the [NAME] on or before the end of her coverage period in 2007. The Appeal Division found that there was nothing about the 2022 MRI Report that was relevant to the question whether the General Division had erred, because that report was from many years after the end of the Applicant’s coverage and long after the Review Tribunal’s decision. Because the 2022 MRI Report was not relevant to whether the General Division had erred, the Appeal Division found that it could not form the basis for permission to appeal. [ 37 ] Again, I appreciate that this reasoning does not include the Appeal Division conducting its own analysis of the application of the res judicata doctrine (including the injustice exception). As previously noted, I understand the Applicant’s arguments in this application for judicial review to be to the effect that, independent of procedural unfairness, her medical history and related documentation support a conclusion that it would be unjust to rely on the Review Decision and the res judicata doctrine to preclude a new appeal. While the list of factors that may inform the application of the injustice exception is not closed, I have difficulty concluding that such arguments fall within any of the guidance afforded by [NAME] as to the scope of the exception to the general principle that a final adjudication on the merits cannot be revisited. [ 38 ] However, I need not make a finding on this point, as the Appeal Division was not asked to address such arguments. As previously noted, the Applicant’s submissions in the Leave Application did not advance arguments of this sort, and it is trite law that an administrative decision cannot be found unreasonable for failing to address arguments with which the decision-maker was not presented (see, e.g., [NAME] v Canada (Citizenship and Immigration) , 2026 FC 596 at para 31 and [NAME] v Canada (Citizenship and Immigration) , 2024 FC 320 at para 26). [ 39 ] As the Respondent submits, the Appeal Division considered the Applicant’s arguments and provided intelligible reasons for concluding that they did not have a reasonable chance of success on appeal. Applying the principles of [NAME] , I find that the Appeal Division is reasonable and withstands judicial review.

VII. Conclusion and Costs [ 40 ] Based on the above conclusion that the Decision is reasonable, my Judgment will dismiss this application for judicial review. While the Respondent has prevailed in the application, it has not claimed costs. As such, my Judgment will not award costs to either party.

JUDGMENT IN T-984-24 THIS COURT’S

JUDGMENT is that: The 2026 Medical Report shall be placed on the Court file but is not admitted into evidence in this application. This application is dismissed. No costs are awarded. "Richard F. Southcott" Judge FEDERAL COURT SOLICITORS OF RECORD DOCKET: T-984-24 STYLE OF CAUSE: [NAME] v ATTORNEY GENERAL OF CANADA PLACE OF HEARING: toronto, ontario DATE OF HEARING: may 19, 2026

REASONS AND

JUDGMENT: Justice Southcott DATED: may 26, 2026 APPEARANCES : [NAME] For The Applicant (ON THEIR OWN BEHALF) [NAME] FOR THE RESPONDENT SOLICITORS OF RECORD : Attorney General of Canada Toronto, Ontario For The Respondent