CITATION: OPSEU v. The Crown, 2026 ONSC 3926
DIVISIONAL COURT FILE NO.: DC-26-28
DATE: 2026-08-13
ONTARIO
SUPERIOR COURT OF JUSTICE
DIVISIONAL COURT
Varpio, Vermette, Brownstone, JJ.
BETWEEN:
ONTARIO PUBLIC SERVICE EMPLOYEES UNION/SYNDICAT DES EMPLOYES DE LA FONCTION PUBLIQUE DE L’ONTARIO
Applicant
– and –
THE CROWN IN RIGHT OF ONTARIO AS REPRESENTED BY THE MINISTRY OF THE SOLICITOR GENERAL
GRIEVANCE SETTLEMENT BOARD
Respondents
Katherine Ferreira and Bennett Morrison for the Applicant
Joohyung Lee, for the Respondent the Crown in Right of Ontario as represented by the Ministry of the Solicitor General
HEARD: June 08, 2026
REASONS FOR DECISION
[1] On April 20, 2020, Ms. Vannaleigh Vlahovich was working as a probation and parole officer in Elliot Lake, Ontario. An offender came to an appointment at the office. Police advised Ms. Vlahovich that the offender was to be arrested in the office. The offender entered the meeting room. Ms. Vlahovich was present when the offender committed suicide with a firearm.
[2] The Crown in Right of Ontario (the “Employer”) notified the Ministry of Labour, Training and Skills Development (“MOL”) of the incident. An MOL inspector investigated and issued three field visit reports and associated orders. The inspector issued a final order on June 25th, 2020.
[3] OPSEU/SEFPO (the “Union”) is the statutory bargaining unit for probation and parole officers. The Union filed a grievance on May 28th, 2020, prior to the release of the MOL inspector’s final order.
[4] At the grievance, arbitrator Sara Slinn heard a preliminary motion wherein the Employer alleged that the grievance ought to be dismissed as a result of the doctrine of issue estoppel. The Employer argued that, inter alia, the inspector had issued orders in the matter that covered the issues to be determined in the grievance. The arbitrator granted that motion.
[5] The Union seeks judicial review of the arbitrator’s decision. It seeks orders quashing and setting aside the decision, remitting the grievance back to the Grievance Settlement Board (“GSB”) for a hearing before a different arbitrator, and such further and other relief as this Honourable Court may deem just and appropriate.
[6] For the reasons that follow, I would dismiss the application.
FACTS
The Incident
[7] On April 20, 2020, Ms. Vlahovich was working at the Elliot Lake probation and parole office. She was to interview an offender. The interview was to occur in a Secure Interview Room (“SIR”). SIR’s featured glass walls that separated offenders and officers, presumably as a means of preventing the spread of COVID. It appears from the record before this court, and no argument was raised to the contrary, that officers and offenders were not actually in the same room. Rather, it appears that two rooms were separated by glass (which was not bulletproof) with an officer in one room and the offender in a SIR. At the time, the probation office did not have lockers for offenders to place their personal items, nor did it have screening machines to detect firearms and/or other weapons.
[8] The Ontario Provincial Police advised Ms. Vlahovich that they would be arresting the offender at the probation office when he attended for his appointment. The offender attended the appointment and the police subsequently entered the SIR. Ms. Vlahovich was present when the offender committed suicide with a firearm.
[9] The Employer notified the MOL of the incident pursuant to its obligations under the Occupational Health and Safety Act, R.S.O., 1990, c. O. 1 (“OHSA”).
The Investigation
[10] The MOL sent an inspector to examine the situation. The inspector issued three field visit reports and associated orders. The first order, dated April 29th, 2020, required the Employer to complete a workplace violence risk re-assessment. The Employer completed such a workplace violence risk re-assessment.
[11] On May 14th, 2020, the inspector issued a second order that held that the Employer’s workplace violence risk re-assessment did not comply with the April 29th, 2020 order. The inspector extended the deadline to allow the Employer to comply with the April 29th, 2020 order.
[12] On May 28, 2020, the Employer submitted a second workplace violence re-assessment. On June 25th, 2020, the inspector issued a final order which found that the second workplace violence risk assessment complied with the April 29th, 2020 order.
The Grievance
[13] On May 28th, 2020, the Union filed a grievance on behalf of Ms. Vlahovich. The grievance claimed that the Employer failed to take all reasonable precautions regarding Ms. Vlahovich’s health and safety in the workplace thereby violating Article 2 (management rights) and Article 9 (health and safety) of the collective agreement (“CBA”).
[14] Article 2 of the CBA states:
For the purpose of this Collective Agreement, the right and authority to manage the business and direct the workforce, including the right to hire and lay off, appoint, assign and direct employees; evaluate and classify positions; discipline, dismiss or suspend employees for just cause; determine organization, staffing levels, work methods, the location of the workplace, the kinds and locations of equipment, the merit system, training and development and appraisal; and make reasonable rules and regulations; shall be vested exclusively in the Employer. It is agreed that these rights are subject only to the provisions of this Collective Agreement.
[15] Article 9 of the CBA states:
The Employer shall continue to make reasonable provisions for the safety and health of its employees during the hours of their employment. It is agreed that both the Employer and the Union shall co-operate to the fullest extent possible in the prevention of accidents and in the reasonable promotion of safety and health of all employees.
[16] The grievance also claimed that the Employer violated the OHSA and other legislation and/or legal principles. The grievance sought an order of full compliance with the governing legislation, a third-party safety audit, the installation of any necessary engineering controls to prevent the introduction or use of firearms in the workplace, and any other remedy required to ensure workplace safety.
The Pre-Existing OLRB Matter
[17] Prior to the Elliot Lake incident, the Employer had been involved in an OLRB matter that had similar factual underpinnings to the case before this court. In that pre-existing matter, the OLRB was considering cases where offenders had brought knives into secure areas of probation and parole offices in Barrie and Newmarket. On October 30, 2020, the OLRB matter was resolved via OLRB memorandum of agreement (the “Memorandum”) and a consent order. The Memorandum addressed the issue of weapons being introduced into secure areas of probation and parole board workplaces. The parties to the Memorandum agreed that
the Employer will continue with its current program of conducting security reviews and risk assessments regarding health and safety precautions and procedures for workers and access controls and weapons at probation and parole offices in Ontario. Without limiting the generality of the foregoing, the security review and risk assessment will continue to address the issue of weapons entering the secure area of probation and parole offices.
[18] The parties to the Memorandum agreed to a process whereby a third-party would review the efficacy, installation, feasibility and use of metal detectors in probation and parole offices. The final report of the third-party review was produced in November 2022.
[19] In July 2024, the Union applied to the OLRB for enforcement of the Memorandum. In that application, the Union alleged that the Employer had breached the Memorandum by failing to follow the required process for the third party review, and that the final report was not responsive to the Memorandum. This enforcement proceeding was ongoing at the time the arbitrator heard preliminary motions in the case before this court.
The GSB Hearing
[20] Prior to the GSB hearing, the Employer brought two preliminary motions. First, the Employer submitted that the grievance ought to be dismissed for issue estoppel, abuse of process and/or collateral attack as the gravamen of the GSB hearing had been dealt with by the MOL inspector. Second, the Employer submitted that the grievance ought to be dismissed for issue estoppel, abuse of process and/or collateral attack in light of the fact that the Memorandum had been incorporated into an OLRB order. In the alternative, the Employer submitted that the grievance ought to be deferred pending further steps in the OLRB matter.
[21] The arbitrator heard the motions, with final written submissions being tendered in September of 2025. On December 10, 2025, the arbitrator held that the matter ought to be dismissed on the basis of issue estoppel. The arbitrator stated that issue estoppel involves a balancing of interests as between the need for finality in litigation and the "public interest in ensuring that justice is done on the facts of a particular case". The arbitrator considered the Supreme Court of Canada’s decisions in Penner v. Niagara (Regional Police Services Board), 2013 SCC 19 and Danyluk v. Ainsworth Technologies, Inc., 2001 SCC 44.
[22] The arbitrator outlined the facts of the case before her, the MOL inspector’s involvement and findings, as well as the facts and outcomes (as they then existed) of the pre-existing OLRB matter involving the Barrie and Newmarket incidents.
[23] The arbitrator then applied the two-part issue estoppel test outlined in Penner. She first identified the pre-conditions to the test, namely:
Whether the same question had been decided;
Whether the judicial decision which is said to create the estoppel was final; and
Whether the parties to the orders were the same.
[24] The arbitrator found that the instant case met the pre-conditions outlined in Penner. The arbitrator held that the grievance and the inspector’s orders answered the same question in that:
(a) both processes involve the same people and circumstances; and
(b) the inspector’s orders and the grievance share the same legal matrix because Articles 2 and 9 of the CBA do not impose material legal obligations on the Employer beyond those imposed by the OHSA.
[25] The arbitrator held that Articles 2 and 9 of the CBA merely incorporate the OHSA. In coming to this conclusion, the arbitrator answered pre-conditions (1) and (3) in the affirmative. Both parties agreed that pre-condition (2) – the finality of the order – was met.
[26] The arbitrator stated that she had a residual discretion to forgo applying the doctrine of issue estoppel where so doing would work an injustice. This discretion was to be applied when considering the non-exhaustive factors outlined in Danyluk.
[27] The arbitrator held that no injustice would flow from the application of the doctrine of issue estoppel in this case. She reviewed the factors described in Danykuk and found that, while the wording of the governing legislation and its purposes suggest that MOL and GSB processes can operate in parallel, in this case the two processes dealt with OHSA compliance and nothing more. The fact that similar (if not identical) issues would be adjudicated by the MOL and GSB processes meant that no injustice would occur from applying the doctrine.
[28] The arbitrator noted that the Union chose not to appeal the inspector’s decision to the OLRB as per s. 61 of the OHSA (and thereby trigger a hearing de novo), which fact contributed to her view that no injustice would arise from the application of the doctrine of issue estoppel. The arbitrator also noted that the Memorandum ensured ongoing compliance with the OHSA.
[29] The arbitrator dismissed the grievance on that basis.
[30] The Union brought this application for judicial review.
POSITION OF THE PARTIES
[31] The Union essentially advanced four arguments before this court:
The arbitrator’s failure to consider an MOL inspector’s inability to make determinations about the CBA was unreasonable;
The arbitrator’s consideration of the wording of the legislation was unreasonable;
The arbitrator unreasonably failed to give due consideration to the effects of sections 50(2) and 51 of OHSA when considering the purpose of parallel proceedings and the effect of mandatory reporting; and
The arbitrator unreasonably failed to consider the potential injustice that arose in the circumstances of this case.
[32] The Employer submits that the arbitrator’s findings were reasonable and that the application should be dismissed as a result.
ANALYSIS
The Law and Relevant Jurisprudence
Standard of Review
[33] All parties agree that the arbitrator’s decision is to be assessed on the standard of reasonableness, as per Canada (Minister of Citizenship and Immigration) v. Vavilov, 2019 SCC 65.
The OHSA
[34] The OHSA is a "critically important piece of public welfare legislation": see Ontario Public Service Employees Union Local 234 v Ministry Community Safety Correctional Services Vanier Centre For Women, 2019 CanLII 14451 (ON LRB) at para. 54. The statute is intended to guarantee reasonable levels of protection for workers' health and safety. Courts and the OLRB have consistently stated that the statute should be interpreted generously and that "narrow or technical interpretations that would interfere with or frustrate the attainment of the legislature's public welfare objectives are to be avoided": see Ontario (Ministry of Labour) v. Hamilton (City), 2002 CanLII 16893 (ON CA) at paras. 16-17.
[35] Section 51(1) OHSA describes an employer’s obligations where a person is killed at a workplace:
51 (1) Where a person is killed or critically injured from any cause at a workplace, the constructor, if any, and the employer shall notify an inspector, and the committee, health and safety representative and trade union, if any, immediately of the occurrence by telephone or other direct means and the employer shall, within forty-eight hours after the occurrence, send to a Director and to the committee, health and safety representative and trade union, if any a written report of the circumstances of the occurrence containing such information and particulars as the regulations prescribe. R.S.O. 1990, c. O.1, s. 51 (1); 2011, c. 1, Sched. 7, s. 2 (7); 2021, c. 34, Sched. 15, s. 7.
[36] Section 54 of the OHSA describes an investigator’s powers:
54 (1) An inspector may, for the purposes of carrying out his or her duties and powers under this Act and the regulations,
(a) subject to subsection (2), enter in or upon any workplace at any time without warrant or notice;
(b) take up or use any machine, device, article, thing, material or biological, chemical or physical agent or part thereof;
(h) make inquiries of any person who is or was in a workplace either separate and apart from another person or in the presence of any other person that are or may be relevant to an inspection, examination, inquiry or test;
(i) require that a workplace or part thereof not be disturbed for a reasonable period of time for the purposes of carrying out an examination, investigation or test;
(p) require the production of any materials concerning the content, frequency and manner of instruction of any training program and inspect, examine and copy the materials and attend any such program. R.S.O. 1990, c. O.1, s. 54 (1); 2011, c. 11, s. 15; 2021, c. 34, Sched. 15, s. 8.
[37] Section 57(1) of the OHSA empowers the inspector to issue orders where the inspector finds that the OHSA has been breached by the employer:
57 (1) Where an inspector finds that a provision of this Act or the regulations is being contravened, the inspector may order, orally or in writing, the owner, constructor, licensee, employer, or person whom he or she believes to be in charge of a workplace or the person whom the inspector believes to be the contravener to comply with the provision and may require the order to be carried out forthwith or within such period of time as the inspector specifies. R.S.O. 1990, c. O.1, s. 57 (1).
[38] Sections 57(3) to 57(5) of the OHSA outline the contents of an inspector’s orders:
(3) An order made under subsection (1) shall indicate generally the nature of the contravention and where appropriate the location of the contravention. R.S.O. 1990, c. O.1, s. 57 (3).
(4) An order made under subsection (1) may require a constructor, a licensee or an employer to submit to the Ministry a compliance plan prepared in the manner and including such items as required by the order. R.S.O. 1990, c. O.1, s. 57 (4).
(5) The compliance plan shall specify what the constructor, licensee or employer plans to do to comply with the order and when the constructor, licensee or employer intends to achieve compliance. R.S.O. 1990, c. O.1, s. 57 (5).
[39] Section 61 of the OHSA outlines the appeal process from an inspector’s order:
61(1) Any employer, constructor, licensee, owner, worker or trade union which considers himself, herself or itself aggrieved by any order made by an inspector under this Act or the regulations may appeal to the Board within 30 days after the making of the order. 1998, c. 8, s. 57 (1).[1]
[40] Section 61(3.6) of the OHSA gives an appellant the right to call evidence and make submissions during an appeal:
(3.6) The Board shall determine its own practice and procedure but shall give full opportunity to the parties to present their evidence and to make their submissions. 1998, c. 8, s. 57 (2).
[41] Section 61(4) of the OHSA outlines the powers of the OLRB on appeal:
(4) On an appeal under this section, the Board may substitute its findings for those of the inspector who made the order appealed from and may rescind or affirm the order or make a new order in substitution therefor, and for such purpose has all the powers of an inspector and the order of the Board shall stand in the place of and have the like effect under this Act and the regulations as the order of the inspector. 1998, c. 8, s. 57 (2).
Issue Estoppel
[42] At paras. 28 and 29 of Penner the majority of the Supreme Court of Canada outlined the test for issue estoppel and described the policy principles underlying the test:
Relitigation of an issue wastes resources, makes it risky for parties to rely on the results of their prior litigation, unfairly exposes parties to additional costs, raises the spectre of inconsistent adjudicative determinations and, where the initial decision maker is in the administrative law field, may undermine the legislature's intent in setting up the administrative scheme. For these reasons, the law has adopted a number of doctrines to limit relitigation.
The one relevant on this appeal is the doctrine of issue estoppel. It balances judicial finality and economy and other considerations of fairness to the parties. It holds that a party may not relitigate an issue that was finally decided in prior judicial proceedings between the same parties or those who stand in their place. However, even if these elements are present, the court retains discretion to not apply issue estoppel when its application would work an injustice.
[43] At paras 30 and 31 of Penner, the majority of the court outlined the policy principles that ought to guide the exercise of this residual judicial discretion:
The principle underpinning this discretion is that "[a] judicial doctrine developed to serve the ends of justice should not be applied mechanically to work an injustice": Danyluk, at para. 1; see also Toronto (City) v. C.U.P.E., Local 79, 2003 SCC 63, [2003] 3 S.C.R. 77, at paras. 52-53.
Issue estoppel, with its residual discretion, applies to administrative tribunal decisions. The legal framework governing the exercise of this discretion is set out in Danyluk. In our view, this framework has not been overtaken by this Court's subsequent jurisprudence. The discretion requires the courts to take into account the range and diversity of structures, mandates and procedures of administrative decision makers; however, the discretion must not be exercised so as to, in effect, sanction collateral attack, or to undermine the integrity of the administrative scheme. As highlighted in this Court's jurisprudence, particularly since Dunsmuir v. New Brunswick, 2008 SCC 9, [2008] 1 S.C.R. 190, legislation establishing administrative tribunals reflects the policy choices of the legislators and administrative decision making must be treated with respect by the courts. However, as this Court said in Danyluk, at para. 67: "The objective is to ensure that the operation of issue estoppel promotes the orderly administration of justice but not at the cost of real injustice in the particular case."
[44] The majority of the court in Penner recognized the following non-exhaustive factors described at paras. 68 to 80 in Danyluk as being relevant to the exercise of this residual discretion:
a. The wording of the statute from which the power to issue the administrative order derives;
b. The purpose of the legislation;
c. The availability of an appeal;
d. The safeguards available to the parties in the administrative procedure;
e. The expertise of the administrative decision maker;
f. The circumstances giving rise to the prior administrative proceedings; and
g. Any potential injustice.
[45] The majority of the Supreme Court of Canada in Penner synthesized these Danyluk factors at paras. 38 and 39 of its decision:
The list of factors in Danyluk merely indicates some circumstances that may be relevant in a particular case to determine whether, on the whole, it is fair to apply issue estoppel. The list is not exhaustive. It is neither a checklist nor an invitation to engage in a mechanical analysis.
Broadly speaking, the factors identified in the jurisprudence illustrate that unfairness may arise in two main ways which overlap and are not mutually exclusive. First, the unfairness of applying issue estoppel may arise from the unfairness of the prior proceedings. Second, even where the prior proceedings were conducted fairly and properly having regard to their purposes, it may nonetheless be unfair to use the results of that process to preclude the subsequent claim.
The Issues Raised by the Union
An Inspector’s Inability to Enforce CBA Violations
[46] The Union submits that the arbitrator failed to consider the inspector’s inability to determine whether the CBA was violated when considering the “same issue” precondition. The Union submits that this failure was unreasonable because CBA violations are central to the grievance arbitration process. As a corollary, the Union argues that the inspector could not enforce the grievor’s terms and conditions of employment as described in the CBA.
[47] As stated in para. 43 of Toronto Police Services Board v. Briggs, 2017 ONSC 1591, the “same question” pre-condition described in Penner requires that the trier “focus on the particular facts of [the] case” and that the trier must engage in a “nuanced, case-by-case approach”. This pre-condition for issue estoppel requires an examination of the substance of the parties’ positions and a determination as to whether there is a real difference as between the questions to be determined: OPSEU v. Ontario (Ministry of Solicitor General), [2025] O.J. No. 1277 at para 28.
[48] In this case, the arbitrator’s determination that there were no possible breaches of the CBA beyond those already addressed by the inspector’s OHSA findings was reasonable. The Union could not point to any issue in this case where an arbitrator could make a decision that was not already covered by the inspector. The arbitrator’s finding was reasonable as a result.
The Purpose of the Statutes
[49] The Union submits that, although the arbitrator correctly reviewed the wording of the relevant statutes, her reasoning, analysis and application of the relevant statutory provisions and jurisprudence was unreasonable. While the arbitrator acknowledged that the legislation and jurisprudence contemplate parallel proceedings, she failed to consider the parties’ reasonable expectations when considering whether to exercise her discretion. The Union submits that, since the grievance was timely, the arbitrator was obliged to weigh the parties’ reasonable expectations when coming to her decision. The failure to do so renders the decision unreasonable.
[50] The Union could not point to any example where the arbitrator’s alleged failure to consider the Union’s procedural expectations was unreasonable save for the fact that the Union felt it could direct the grievance process more so than it could an MOL inspection.
[51] While this ability to direct a grievance may amount to a procedural difference, the arbitrator’s alleged failure to consider same does not render the decision unreasonable. The Union did not point to how the outcome of the grievance would be materially different than the outcome of the MOL investigation, given its ability to help direct the former. Had the Union been able to identify such a material difference, the arbitrator’s alleged failure to give weight to the Union’s expectations may have been of some concern. However, the Union’s inability to point to any specific issue beyond its ability to “drive the bus” is of little consequence and, as such, the arbitrator’s decision not unreasonable.
The Alleged Failure to Consider the Effect of Mandatory Reporting Under the OHSA
[52] In her reasons, the arbitrator recognized that s. 51 of the OHSA required the Employer to report the fatality to the MOL, thereby triggering an investigation. The Union submits that the arbitrator failed to analyze how the policy reasons underlying this mandatory reporting inform the purpose of the OHSA. The arbitrator did not adequately analyze whether that purpose differs from the purpose of grievance arbitration. The Union submits that this policy comparison is a necessary element of the Penner analysis. The failure so to do renders the arbitrator’s decision unreasonable.
[53] This failure, per the Union, is highlighted in the arbitrator’s reliance upon para. 68 of Re: OPSEU and Ontario (Ministry of the Solicitor General), 2024 CanLII 52265 (upheld by this court at 2025 ONSC 1801), which states:
In these circumstances there is little unfairness to the Union and its members to, having chosen the inspector route to deal with their health and safety concerns, require them to follow that process through rather than to choose a different process: the grievance and arbitration procedure. [emphasis added]
[54] In the instant case, the Union had no choice of procedure as the Employer was required to report the fatality as per s. 51(1) of the OHSA. As such, the Union submits that the rationale upon which the arbitrator relied is inapplicable. The Union further submits that the arbitrator’s reliance upon this rationale becomes especially problematic when one considers para. 161 of the arbitrator’s reasons which, as per the Union, effectively forecloses parallel proceedings when s. 51 OHSA mandatory reporting is triggered:
In a case different than the present one, it may well be possible for a union to grieve the same incident that has been the subject of an inspector’s decision, including where that inspection is initiated by mandatory reporting. For instance, where the grievance claims are different or broader than the issues determined by the inspector – enforcement of the OHSA – then the grievance may well be able to proceed. In those circumstances, the precondition for issue estoppel that the two proceedings address the same question would not likely be satisfied. Or, in a case where there is unfairness in the Inspection or its circumstances, it may be appropriate for discretion to be exercised not to apply issue estoppel. However, those are not the situations we have here.
[55] When considering the Union’s submission, it must be remembered that the failure to deal with a particular issue does not necessarily render a decision unreasonable. Rather, that issue must cause the reviewing court to lose confidence in the outcome reached by the decision-maker: see Vavilov, at para 122. In this case, the only procedural or substantive differences between the MOL inspection and a grievance is that the Union does not have procedural control over an inspection, whereas it has some modicum thereof in a grievance. As noted above, the Union did not explain why this difference was of any meaningful import. I also note that the arbitrator did not state that parallel proceedings could never take place. Rather, she stated that parallel proceedings should not take place in this case and provided examples where it might. As such, the difference described by the Union appears meaningless, and the alleged failure to analyze the policy reason underlying mandatory reporting does not cause me to lose confidence in the arbitrator’s decision.
[56] It is also important to note that the arbitrator effectively stated that, all else being equal, filing a grievance whose outcome would entirely overlap the findings of an MOL inspection would be duplicative and wasteful. Her logic highlights the fact that parallel proceedings in the absence of material differences effectively creates litigation for its own sake. The suggestion that such litigation may have any merit runs contrary to the principle of judicial economy and the arbitrator was not unreasonable for highlighting this issue.
The Alleged Failure to Consider Injustice
[57] The Union concedes that the arbitrator correctly relied upon Danyluk when she held at para. 155 of her reasons that potential injustice is the most important factor to consider when deciding whether to exercise her residual discretion. Para. 80 of Danyluk makes clear that a trier must “stand back and, taking into account the entirety of the circumstances, consider whether application of issue estoppel in the particular case would work an injustice”.
[58] The Union essentially submits that the arbitrator acted unreasonably when she mentioned the Memorandum that resolved the pre-existing Barrie and Newmarket cases. Because the incident before this court was not before the OLRB when it generated the Memorandum, the arbitrator’s consideration of the Memorandum created an injustice. The arbitrator was unfair when she held that the ongoing obligations on the Employer (as created by the Memorandum) would assist in ensuring that there was no “real injustice” visited upon the Union or the griever.
[59] Again, the Union failed to explain how the fact that the Elliot Lake incident occurred after the signing of the Memorandum rendered the arbitrator’s application of issue estoppel unjust. The Union could not identify how any injustice flowed from the failure to conduct a full grievance hearing when the issues to be resolved had already been dealt with in the MOL inspection (as well as by the Memorandum).
[60] Further, if it thought the inspector’s decision was unjust, the Union could have appealed that decision and had a hearing de novo. It chose not to pursue that avenue. As such, and since the Memorandum addresses ongoing safety concerns (which concerns were the gravamen of the arbitration), the arbitrator was not unreasonable in finding that no injustice would flow from applying the doctrine of issue estoppel given the multiplicity of similar proceedings.
CONCLUSION
[61] For the foregoing reasons, I would dismiss the application.
[62] As per agreement of the parties, the Employer is entitled to $5,000 in costs (all-inclusive) payable within 90 days.
Varpio J.
I agree.
Vermette J.
I agree.
Brownstone J.
Released: August 13, 2026
CITATION: OPSEU v. The Crown, 2026 ONSC 3926
ONTARIO
SUPERIOR COURT OF JUSTICE
DIVISIONAL COURT
Varpio, Vermette, Brownstone, J.J.
BETWEEN:
OPSEU
- and –
THE CROWN
REASONS FOR DECISION
Released: August 13, 2026