On November 10, 2023 the Supreme Court of Canada (“SCC”) released its decision in R v. Greater Sudbury (City) (“Greater Sudbury”)[1] finding that an “owner” of a construction project can be considered an “employer” under the Occupational Health and Safety Act (the “OHSA” or the “Act”) of Ontario.[2] This decision showcases a paradigm shift in how project owners, constructors, and employers perceive and undertake their health and safety obligations under the OHSA. It underscores the importance of a collective approach to workplace safety and mandates a higher level of vigilance and compliance from all parties involved in a construction project. Below, we consider some of the key takeaways of this decision.


The City of Greater Sudbury (the “City”) hired Interpaving Limited (“Interpaving”) to repair a downtown water main (the “Project”). The contract between the City and Interpaving stipulated that Interpaving would oversee the entire Project. This included acting as the “constructor”  as defined by the OHSA, and guaranteeing compliance with the standards set forth in the Act. During the project, an Interpaving employee, driving a road grader in reverse, fatally struck a pedestrian while she crossed an intersection within the construction zone. It was determined that the project site lacked necessary safety measures, such as a fence and signaller, as mandated by regulations, leading to the Ministry of Labour (the “Ministry”) charging the City and Interpaving with violations of Construction Projects, O. Reg. 213/91, contrary to section 25(1)(c) of the OHSA. The Ministry charged the City on the basis that the City was a “constructor” and an “employer” under the OHSA.[3]

Procedural History

The Ontario Court of Justice acquitted the City, finding that Interpaving exercised direct control over the workers and the Site, thus excluding the city from the definition of an employer. The trial judge also noted that if the City was an employer, it had acted with due diligence, thus acquitting the City of all charges.[4]

The Crown appealed to the Ontario Superior Court of Justice (“ONSC”), arguing that the City was a “constructor” on the Project due its level of control, however, this argument was rejected. The ONSC found that the City’s contract with Interpaving was typical for municipal maintenance work, and the City’s involvement, including quality control, did not make it a “constructor” or “employer” under the OHSA, leading to a dismissal of the Crown’s appeal.[5]

Following this, the Ontario Court of Appeal (ONCA) granted the Crown leave to appeal to determine if the City was an employer under the OHSA, based on the definition of employer as one who employs workers. The ONCA found that the City was an employer, as it had employed inspectors at the project site for tasks such as quality assurance, irrespective of its control over the project. The issue of the City’s due diligence defense was referred back to the ONSC for further consideration.[6]

The Decision of the Supreme Court of Canada

In a split decision, four justices agreed (with the other four judges in dissent, given that Justice Brown did not participate in the judgment) with the Court of Appeal that the City was indeed an employer and had breached its duty under section 25(1)(c) of the OHSA. Because a majority is required to overturn a lower court decision, the fact that the court was evenly split meant that there was no majority and that the appeal was therefore dismissed.

The SCC found that the Act is designed to offer a reasonable level of protection for worker health and safety at the workplace and is recognized as a remedial public welfare statute, aimed at ensuring a minimum level of worker protection. Citing to Ontario (Ministry of Labour) v Hamilton (2002), the SCC emphasized that the Act should be interpreted generously to promote public health and safety, avoiding narrow or technical interpretations that could hinder its public welfare objectives.[7]

Further, the SCC found that the Act achieves its public welfare purpose by allocating health and safety duties among various workplace parties, including constructors, employers, and owners, emphasizing that these duties are often concurrent and overlapping, ensuring multiple parties are responsible for the same safety measures. This approach is described as the “belt and braces” strategy in occupational health and safety, ensuring worker protection through multiple safeguards. If one system fails, another might compensate, rendering the protection of workers a collective responsibility.[8] Following this approach, the SCC held that multiple workplace entities are accountable for health and safety breaches, and they cannot use others’ failures as an excuse for their own negligence. Every workplace participant must ensure a safe working environment.[9]

Since a breach of s. 25(1)(c) is a strict liability offence, the Ministry only needed to prove the actus reus beyond a reasonable doubt to ground a conviction, which, according to the SCC, had been done. Importantly, the Ministry was not required to demonstrate that the City had exercised control over the workers or workplace to establish a breach. The Court determined that the Act’s text and context indicated a legislative intent to deliberately focus on the employer’s connection to the workplace rather than control over individual workers.[10] This broad interpretation of “employer” and their duties should be viewed as complementary within the Act’s framework. Furthermore, the presence of a due diligence defense under section 66(3)(b) is significant. This defense acts as a safeguard, allowing employers who breach section 25(1)(c) to avoid penalties if they can prove they took all reasonable steps to prevent the breach. The SCC found that imposing a control requirement in this context could undermine the Act’s public welfare objective of establishing shared responsibility.[11]

In considering whether the City had successfully demonstrated due diligence under section 66(3)(b) on a balance of probabilities, the SCC opined that here, control was a relevant factor. An employer can argue that its lack of control over the workplace or workers indicates it took all reasonable steps under the circumstances. This approach addresses fairness concerns about imposing liability for breaches caused by others. Factors for consideration include the accused’s degree of control, whether control was delegated to a constructor, the evaluation of the constructor’s compliance abilities, and the monitoring and supervision of the constructor’s work.[12]

In the case at hand, the City was deemed an employer of both the quality control inspectors it directly employed and dispatched to the construction project, and of Interpaving.  As such, the City was obligated under section 25(1)(c) to ensure prescribed measures and procedures were implemented at the worksite. The failure to implement required safety measures, such as fencing and signallers, on the accident date meant that the City, as an employer, committed an offence under section 25(1)(c).


The Supreme Court of Canada’s decision in Greater Sudbury carries significant implications for the construction industry, particularly with respect to how project ownership and health and safety responsibilities are viewed under the OHSA. The following takeaways highlight these impacts.

Expanded Scope of ‘Employer’ Under OHSA: The ruling establishes a broad interpretation of what constitutes an ’employer’ under the OHSA. By finding that the City, as the project owner who employed inspectors for quality assurance, was an ’employer’, the SCC effectively expanded the scope of this definition. This implies that any project owner, irrespective of their direct control over the project or workers, can be deemed an employer if they have a contractual relationship with employees or contractors at the project site. This expansion is pivotal for project owners who may not be directly involved in day-to-day operations but have a contractual nexus to the project. They must now be more vigilant about health and safety compliance, understanding that their connection to the workplace, not control over it, determines their responsibility under the Act.

‘Belt and Braces’ Strategy in Workplace Safety: The decision emphasizes the ‘belt and braces’ approach to occupational health and safety. The SCC’s interpretation reinforces the idea that multiple parties can be concurrently responsible for the same safety measures, ensuring a collective responsibility for worker protection. This approach indicates that failures by one party cannot be used to absolve others from their safety obligations. For the construction industry, this translates to a more collaborative approach to safety, where constructors, employers, and owners must work in tandem to ensure compliance with safety regulations. This landmark ruling may encourage a culture of shared responsibility, potentially leading to more rigorous safety protocols and collaboration in the industry.

Due Diligence Defence and its Implications: The SCC’s decision also sheds light on the due diligence defence under section 66(3)(b) of the Act. While this defence acts as a safeguard for employers who can prove they took all reasonable steps to prevent a breach, the ruling clarifies that control is a relevant factor in this context. In cases where an employer lacks direct control over the workplace or workers, demonstrating due diligence becomes crucial. Project owners and employers in the construction industry should be mindful of this aspect and should consider adopting more proactive and comprehensive safety measures and oversight mechanisms. They will need to ensure that not only are safety measures in place, but that they are actively monitoring and evaluating the compliance abilities of contractors and constructors to reinforce their due diligence obligations.

It is likely that this decision extends beyond the borders of Ontario and has potential implications for similar workplace health and safety legislation in other Canadian provinces. In British Columbia, for example, the Occupational Health and Safety Regulation (the “Regulation“)[13] states that its purpose is aimed at promoting occupational health and safety and protecting workers and others from work-related risks. The Regulation also expressly stipulates that compliance with its requirements is not just an end in itself but serves as a foundational aspect of building an effective health and safety program. It emphasizes cooperation between workers and employers to resolve workplace health and safety issues. The SCC’s decision in Greater Sudbury highlights the necessity of interpreting such regulations to advance public welfare and health and safety goals. This approach aligns with the Regulation’s objective in British Columbia, where the focus is on creating a collaborative and comprehensive safety culture rather than merely adhering to technical compliance.

Similarly, the definition of ’employer’ under the OHSA shares parallels with that in Alberta’s Occupational Health and Safety (OHS) Act[14]. Both Acts encompass a range of relationships, including those involving contractors and subcontractors, and do not depend on direct control over workers. This similarity suggests that the principles set out in Greater Sudbury are likely to be pertinent in interpreting the scope of ’employer’ in Alberta and potentially in other provinces as well. These interpretations imply a broader understanding of employer responsibilities, emphasizing the collective role in ensuring workplace safety.


[1] 2023 SCC 28 [“Greater Sudbury“].

[2] R.S.O. 1990, c. O.1.

[3] R. v. Greater Sudbury (City), 2019 ONSC 3285 [Sudbury].

[4] Greater Sudbury, supra note 1 at para 3.

[5] Sudbury, supra note 3 at paras 28-37.

[6]  Ontario (Labour) v. Sudbury (City), 2021 ONCA 252.

[7] Greater Sudbury, supra note 1 at para 8.

[8] Ibid at paras 10-11, citing Ontario (Ministry of Labour) v Enbridge Gas Distribution Inc., 2010).

[9] Ibid.

[10] Ibid at paras 17-22.

[11] Ibid at para 37.

[12] Ibid at paras 49-60.

[13] BC Reg 296/97.

[14] SA 2020, c O-2.2

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