Constructor Liability in Ontario Construction: Lessons from the Sudbury Case

Ontario law now clearly recognizes that a project can have both a constructor and an owner-employer concurrently responsible for safety. 

Introduction

In Ontario’s construction industry, the legal designation of “constructor” carries significant safety responsibilities and liabilities. Many business owners and project managers mistakenly assume that hiring an independent contractor insulates them from safety obligations. A recent court ruling involving the City of Greater Sudbury has challenged that assumption, highlighting how even owners can be held liable under the Occupational Health and Safety Act (OHSA) and Ontario Regulation 213/91 (Construction Projects). This article provides an in-depth analysis of the Sudbury case and offers practical guidance on avoiding unintended constructor status. We will clarify what a “constructor” is in law, outline the duties that come with this role, and share compliance tips for owners, senior management, and safety professionals to manage projects without incurring unexpected legal liability.

The City of Sudbury Court Ruling: What Happened and Why It Matters

In R. v. Greater Sudbury (City) – a case stemming from a 2015 road construction project – the City had contracted a company (Interpaving Limited) to perform water main repairs, explicitly naming that company as the project’s constructor (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology) (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology). Tragically, a pedestrian was struck and killed by a reversing road grader at the site while no traffic signaller was present and no protective fencing separated the site from the public intersection (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology). These safety measures were required by Ontario’s construction safety regulations, yet they were absent. The contractor was prosecuted and convicted for failing, as an employer, to ensure that these prescribed measures and procedures (e.g. having a signaller and fencing) were carried out, contrary to OHSA section 25(1)(c) ( Defining roles on the jobsite ).

What makes the Sudbury case a landmark is that the City – as the project owner – was also charged under OHSA for the same safety lapses. Prosecutors alleged that the City was both a “constructor” and an “employer” as defined by OHSA, and therefore bore parallel responsibility for the project’s safety shortcomings (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology) (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology). The City argued in its defense that it had hired a competent constructor and was only involved in quality control, not active construction management, and thus should not be considered a constructor or employer in this context. In the initial trial, the Ontario Court of Justice agreed, finding the City was neither a constructor nor an employer on the project and therefore owed no duties under OHSA (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology). However, the Crown (Ministry of Labour) appealed this outcome, setting off a series of legal battles that went all the way to the Supreme Court of Canada.

On appeal, the legal tide turned. The Ontario Court of Appeal ruled unanimously that the City of Sudbury did meet the OHSA definition of an “employer.” By contracting for the services of workers (via the construction firm) and by having its own staff (city inspectors) on site, the City fell within the broad statutory definition of employer and thus was subject to employer duties (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology). The Court of Appeal held the City liable under OHSA section 25(1)(c) – the general duty for employers to ensure prescribed safety measures are carried out – for the lack of a signaller and fencing, “unless the City was able to establish a due diligence defence.” (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology) In other words, the owner could be held responsible for the safety violations on its project despite having a third-party constructor, unless it could prove it took all reasonable precautions to prevent those violations.

The City further appealed to the Supreme Court of Canada (SCC). In November 2023, the SCC issued a split decision (4–4 tie) that upheld the Court of Appeal’s finding that the City was an employer under OHSA (Court rules in City of Sudbury's favour on issue of due diligence | Canadian Occupational Safety). (In a tie, the lower court’s decision stands.) This outcome sent a strong message: in Ontario, a project owner can indeed be an “employer” in the eyes of the law, even when a general contractor is appointed as constructor. The SCC stressed, however, that each case will be fact-specific and that an owner’s level of control over the work and its safety efforts are relevant not to whether it is an employer, but to whether it exercised due diligence (Court rules in City of Sudbury's favour on issue of due diligence | Canadian Occupational Safety). The Court noted that OHSA is “protective legislation” to be interpreted broadly, and multiple parties on a project can have overlapping safety duties (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology). Simply put, hiring a contractor does not absolve an owner of all responsibility – certain duties may overlap between constructors, employers, and owners.

Finally, in 2024, an Ontario Superior Court judge reviewed the City’s due diligence defense (as directed by the Court of Appeal’s remittance). The court dismissed the Crown’s appeal and concluded that the City had exercised appropriate due diligence in this case (Court rules in City of Sudbury's favour on issue of due diligence | Canadian Occupational Safety). Key to this finding was evidence that the City had carefully selected an experienced constructor, clearly delegated safety responsibilities to that constructor, and monitored the work at a high level without micromanaging the project (Court rules in City of Sudbury's favour on issue of due diligence | Canadian Occupational Safety). In the words of the decision, the City “acted with appropriate due diligence in its role as an owner” by hiring a competent third-party constructor and not interfering in day-to-day safety management, proving that owners “can fulfill their due diligence obligations without having to exercise daily control over a construction project.” (Court rules in City of Sudbury's favour on issue of due diligence | Canadian Occupational Safety)

Implications for Owners, Managers, and Safety Professionals

The Sudbury ruling has significant implications for business owners, municipal authorities, project managers, and safety professionals in Ontario’s construction sector. It confirms that an owner who hires a general contractor is not automatically insulated from liability. Even if you avoid being labeled a “constructor” (by contracting one), you may still be considered an “employer” under OHSA if you have contracted workers on site or have your own staff present (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology). That designation brings legal duties that can be enforced with heavy fines or other penalties if breached. As Norm Keith (a prominent OHS lawyer) observed, this is a watershed moment: owners now face “significant legal risk for health and safety enforcement and prosecution” in situations where previously only constructors or contractors would have been targeted ( Defining roles on the jobsite ).

For project managers and safety professionals, the case underscores the importance of clearly defining roles and responsibilities on a project. It also highlights the critical need for due diligence practices: selecting qualified contractors, setting out safety expectations in contracts, and maintaining oversight of safety performance. Owners cannot simply “hand off” a project and turn a blind eye to safety—if something goes wrong, the question will be asked: Did the owner do all that was reasonable to prevent this? The Sudbury case shows that courts will hold owners to account on that question, even while recognizing that owners should not usurp the constructor’s on-site control. The balance is delicate: exercise enough oversight to ensure safety compliance, but not so much as to start directing the work and thereby risk being deemed the constructor. The next sections will clarify how the law defines a “constructor” and offer guidance on walking this line.

Who Is a ‘Constructor’ Under Ontario’s OHSA?

Ontario’s Occupational Health and Safety Act provides a specific definition of “constructor.” Under OHSA section 1(1), a constructor “means a person who undertakes a project for an owner and includes an owner who undertakes all or part of a project by himself or by more than one employer.” ( My Responsibilities as a Contractor ) In practical terms, the constructor is the party with overall control of the construction project. This is most often a general contractor – the entity hired to coordinate and oversee all work on site – but it could also be the owner themselves if they choose to manage the project or if they retain multiple contractors directly. Importantly, OHSA’s definition explicitly says an owner can become the constructor if the owner undertakes the work “by more than one employer.” In other words, if an owner hires multiple independent contractors to work on the same project (without one being in charge of the others), the law deems that owner to be the constructor ( Practice Advisory Knowledge Base - FAQ.05 OHSA - When is an Owner a Constructor? ). This prevents a scenario where no single party is coordinating safety – someone will always be the constructor by default, and if it’s not a general contractor, it’s the owner. For example, the Ontario Association of Architects cautions that “If there is more than one contractor on site (not subcontractors) then no one contractor has control and [OHSA] declares the owner to be the constructor.” ( Practice Advisory Knowledge Base - FAQ.05 OHSA - When is an Owner a Constructor? )

However, owners who hire a general contractor should note an important clarification in the law. Section 1(3) of OHSA provides that an owner is not deemed a constructor solely because they have engaged an architect, engineer, or other person “to oversee quality control” at the project (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology). This provision allows owners to have consultants or inspectors monitoring the work for compliance and quality without automatically absorbing constructor duties. The tricky part is determining when an owner’s involvement crosses the line from legitimate oversight into the territory of actually “undertaking” or controlling the project. Courts have wrestled with this distinction: the Sudbury trial judge, for instance, examined whether the City’s actions (dispatching police for traffic control, quality inspections, site meetings, etc.) went beyond quality control and into active control of the work (Worklaw® Network - Ontario: The Fine Line between “Owner” and “Constructor”). In that case, the evidence showed the City did not invoke any contractual powers to take over the project and only raised safety concerns through the contractor’s management – actions which the court held did not make the City a constructor (Worklaw® Network - Ontario: The Fine Line between “Owner” and “Constructor”). The takeaway is that courts will look at the “reality on the ground” of who is directing the work and safety: simply reserving a right to intervene or having staff on site is not enough to make an owner a constructor if those rights aren’t actually exercised (Worklaw® Network - Ontario: The Fine Line between “Owner” and “Constructor”). But if an owner does start actively managing multiple trades or dictating safety measures directly to workers, the owner may be treated as the constructor regardless of what the contract says.

Legal Duties of a Constructor under OHSA and Regulation 213/91

Being a constructor carries onerous obligations. OHSA section 23(1) spells out the core responsibilities of a constructor on a project:

• Carry Out Safety Measures: “A constructor shall ensure, on a project undertaken by the constructor, that the measures and procedures prescribed by [the OHSA] and the regulations are carried out on the project.” ( My Responsibilities as a Contractor )

• Ensure Compliance by Everyone: The constructor must ensure “every employer and every worker performing work on the project complies with [OHSA] and the regulations.” ( My Responsibilities as a Contractor ) In effect, the constructor oversees all other parties (subcontractors, workers, etc.) to enforce safety rules.

• Protect Worker Health and Safety: The constructor shall ensure “the health and safety of workers on the project is protected.” ( My Responsibilities as a Contractor ) This is a broad, catch-all duty making the constructor the prime guarantor of site safety.

  
  

Additionally, constructors have administrative duties such as submitting a Notice of Project to the Ministry of Labour before work begins (for projects of a certain scale), as required by OHSA 23(2) and the Construction Projects regulation ( My Responsibilities as a Contractor ). They must also post appropriate signage and ensure required equipment, training, and supervision are in place per O. Reg. 213/91. For instance, the regulation mandates that every project have proper fencing or barriers to protect the public, appropriate traffic control (like signallers or traffic protection plans) when work occurs near roadways, fall protection systems for work at heights, trench safety measures, and so on. The constructor is the party responsible for making sure all those “prescribed” safety measures are implemented. If regulators find violations – say, missing guardrails or inadequate traffic control – the constructor will be the primary target of enforcement under these provisions.

It’s worth noting that owners who become constructors assume all these same duties. They cannot defer blame by saying they didn’t know the rules; the law expects a constructor to be sufficiently competent in construction safety management. Courts have made clear that you “cannot contract out of the OHSA” – an agreement between an owner and contractor on paper does not override the reality of who is controlling safety on the ground (Worklaw® Network - Ontario: The Fine Line between “Owner” and “Constructor”). If you are by law the constructor, you are liable for any safety lapses by any party on the site. This is why most prudent owners avoid being the constructor unless they are fully prepared to manage all safety aspects of a project. The Sudbury case demonstrates how an owner can be pulled into liability even when they thought those duties rested with someone else. While the City was found not to be the constructor (because it never truly took control of the project), the fact that the Crown alleged constructor status and the case had to be litigated up to the Supreme Court shows the high stakes of these role definitions (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology).

Overlapping Roles: ‘Owner’, ‘Constructor’, and ‘Employer’ – Understanding the Differences

To navigate constructor liability, owners must understand the different legal roles on a construction project under OHSA:

• Owner – The person or entity having title to the property or who contracted for the work. Owners have relatively limited duties under OHSA (e.g. to provide a list of designated substances on site, and to not interfere with compliance) (Worklaw® Network - Ontario: The Fine Line between “Owner” and “Constructor”). An owner can transfer the constructor role to another party via contract, but cannot escape being an “employer” if they meet that definition, nor can they ignore their residual duties as owner.

  
  

• Constructor – The party with overall control of the project’s construction phase, responsible for coordinating safety and compliance (often the general contractor, as discussed). There can only be one constructor for a project at any given time. All other contractors and workers on site answer to the constructor for safety matters. If an owner does not explicitly appoint a constructor and instead hires multiple contractors, by default the owner becomes the constructor ( Practice Advisory Knowledge Base - FAQ.05 OHSA - When is an Owner a Constructor? ).

  
  

• Employer – In OHSA, “employer” is defined very broadly to include not only those who employ workers directly, but also anyone who “contracts for the services of one or more workers” (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology). This means when an owner hires a contracting company, the owner is considered an employer of the workers of that company for the purposes of OHSA. The owner may also have its own employees on site (for example, engineering inspectors, project managers, or maintenance staff), which makes it a direct employer as well. Multiple employers can therefore exist on the same project – the constructor itself is an employer of its crew, each subcontractor is an employer of their workers, and the owner can be an employer too. Each employer has certain duties under OHSA section 25 and 26, such as ensuring equipment is safe, measures in the regulations are followed, and informing workers of hazards. These duties overlap with the constructor’s duties, which is intentional – the law creates a web of responsibility to ensure no aspect of safety falls through the cracks (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology).

  
  

A key insight from the Sudbury case is how an owner can simultaneously be just an “owner” for some purposes and an “employer” for others. The City had contracted out the project, thereby avoiding being the constructor, but it still had its own inspectors (employees) attending the site and had in effect contracted for the construction services – thus it was held to be an employer (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology). The Supreme Court Justices noted that if an owner fits the literal definition of employer, they must carry the corresponding duties, even if exercising those duties requires a delicate balancing act with the constructor’s role (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology. The Court rejected the notion that an owner needs a certain level of control over the workplace to be deemed an employer – control is relevant to due diligence (what the owner could reasonably do), but not to the mere fact of being an employer under the statute (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology). In short, Ontario law now clearly recognizes that a project can have both a constructor and an owner-employer concurrently responsible for safety. Owners cannot assume that hiring a constructor transfers all safety obligations away. As the IHSA (Infrastructure Health and Safety Association) bluntly summarized, this court decision “means construction project owners may also be employers under the OHSA,” which “puts them at significant legal risk for health and safety enforcement… for the first time.” ( Defining roles on the jobsite ) ( Defining roles on the jobsite )

For safety professionals and managers, the message is to treat owners as part of the safety system. Ensure that owners are aware of their obligations as employers: for example, an owner should ensure its own employees (like site inspectors or managers) are trained and follow safety requirements, and that they coordinate with the constructor on safety matters. Owners should also verify that safety “measures and procedures prescribed” (per OHSA 25(1)(c)) – which largely come from O. Reg. 213/91 – are being implemented on the project. If they see critical safety measures (like trench supports, fall protection, traffic control, etc.) being neglected, they need to raise those issues through the proper channels. The Sudbury case actually showed that an owner can speak up about safety without automatically taking on the constructor role. The court there commended the City’s inspector for intervening when he noticed the contractor working without required police traffic control at an intersection two weeks before the fatality (Worklaw® Network - Ontario: The Fine Line between “Owner” and “Constructor”). The inspector contacted the contractor’s senior representative, who then corrected the issue – this was cited as a positive example of the owner addressing safety “in an appropriate manner” through the constructor, and the court warned that penalizing such actions would be counter-productive (Worklaw® Network - Ontario: The Fine Line between “Owner” and “Constructor”). The lesson is that owners should not shy away from raising safety concerns; rather, they should do so in a way that respects the constructor’s primary role. This kind of active yet appropriate engagement is actually a part of the owner’s due diligence, which brings us to how owners can protect themselves from liability.

Practical Compliance Guide: How to Avoid Unintended Constructor Designation and Liability

Avoiding liability begins with avoiding the role of constructor unless you are truly prepared to take it on. Here are practical steps and best practices for owners, senior managers, and safety professionals to ensure you don’t unintentionally become a “constructor” – and to fulfill your legal duties as an owner or employer – under Ontario law:

1. Designate a Single Constructor for the Project: The simplest way to avoid being deemed a constructor is to hire one reputable general contractor to oversee the entire project. Do not split the work among multiple prime contractors working independently. If you have more than one contractor on site at the same time, you as the owner will likely be considered the constructor by law ( Practice Advisory Knowledge Base - FAQ.05 OHSA - When is an Owner a Constructor? ). Ensure your construction contracts explicitly appoint the contractor as “constructor” for OHSA purposes, and that the contractor accepts in writing the duty to be in full control of the project’s safety. While you cannot contract out of your legal responsibilities, a clear contract can help establish the intended roles and will be respected by courts so long as it reflects reality (Worklaw® Network - Ontario: The Fine Line between “Owner” and “Constructor”). Always verify that the contractor has the capacity to carry out constructor duties (experience, knowledge, resources) before hiring them.

2. Avoid Direct Control of Subcontractors or Site Activities: Once you have a constructor in place, let them do their job. Do not give orders directly to subcontractors or workers on site – all instructions should flow through the constructor’s supervisors. If the owner’s personnel start directing trades or scheduling and sequencing work between contractors, the owner may be seen as undertaking part of the project themselves. As one legal expert put it, the line between permissible “quality control” and impermissible “directing work” is crucial (Worklaw® Network - Ontario: The Fine Line between “Owner” and “Constructor”). Owners should refrain from actions that could be interpreted as taking over coordination of the work. For example, do not independently schedule multiple contractors’ work or physically coordinate their tasks – that’s the constructor’s role. If you need something addressed, communicate the issue to the general contractor’s project manager, not to the workers directly (Worklaw® Network - Ontario: The Fine Line between “Owner” and “Constructor”). Maintain a “hands-off” approach in daily operations: attend meetings as an observer or for progress info, but let the constructor run toolbox talks, supervise safety, and handle worker discipline. Retaining contractual rights to step in (for example, the right to take over if the contractor breaches safety requirements) is fine – just don’t exercise those rights unless absolutely necessary (and if you do, recognize that you may then assume constructor duties from that point). In Sudbury, the contract had such a clause allowing the City to assume control if needed, but the City never invoked it, which helped prove they hadn’t become the constructor (Worklaw® Network - Ontario: The Fine Line between “Owner” and “Constructor”).

3. Engage in Active Oversight Without Taking Over: Being hands-off in terms of control doesn’t mean ignoring safety. Owners and their safety professionals should establish a system of monitoring the project’s safety performance. This can include: regular site visits or audits by the owner’s representative, reviewing safety meeting minutes, and requiring periodic status reports on safety compliance. The key is that these activities should be framed as verification and oversight, not directing the means of work. If an owner’s site inspector notices a safety hazard or non-compliance with the regulations, they should bring it up – but do so with the constructor’s management. For instance, if during a site walk you see a worker working at height without fall protection, you should immediately inform the constructor’s site supervisor or project manager and formally request corrective action. Document these communications (e.g. by writing an email or a memo to the constructor summarizing the concern and asking for it to be addressed). This creates a record of the owner fulfilling its due diligence as an employer concerned for safety, without the owner directly bossing the worker. In the Sudbury case, the court explicitly approved of the owner’s inspector shutting down a portion of work by contacting the contractor’s senior staff to do so when a serious safety lapse (no traffic control at a live intersection) was observed (Worklaw® Network - Ontario: The Fine Line between “Owner” and “Constructor”). The court noted that an owner should intervene through the constructor in such scenarios and should even be commended for doing so, as it improves safety (Worklaw® Network - Ontario: The Fine Line between “Owner” and “Constructor”). The lesson is to channel all safety interventions through the constructor’s chain of command. This allows you to ensure issues are corrected while respecting the constructor’s role. It also positions you well to assert a due diligence defense later, as you can show you did raise concerns and not simply turn a blind eye.

4. Perform Due Diligence in Contractor Selection and Planning: A huge part of avoiding liability is done before the project starts. Due diligence for owners means carefully selecting contractors who are capable of managing health and safety. Investigate the prospective constructor’s safety record, ask for their health and safety policy, procedures, and proof of adequate training for their staff. Verify that they are in good standing with workers’ compensation and have no recent convictions under OHSA. If possible, include in the bidding or negotiation process an assessment of how the contractor plans to manage key risks on your project (for example, ask how they will handle traffic control, public protection, fall hazards, etc., specific to the work). The Supreme Court suggested that owners should “evaluate the constructor’s ability to ensure compliance with the Regulation before deciding to contract for its services.” (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology). Choosing a competent constructor is not just prudent – it forms part of the owner’s due diligence defense if something goes wrong despite those precautions. Similarly, at the contract stage, clearly require the constructor to follow OHSA and all applicable regulations, and maybe even outline specific safety provisions (like “contractor shall ensure a traffic control plan with police or signallers as required by O. Reg 213/91”). By explicitly delegating safety responsibilities to an expert contractor, an owner demonstrates it took reasonable steps to have the project run safely (Worklaw® Network - Ontario: The Fine Line between “Owner” and “Constructor”). Remember, if you lack construction safety expertise in-house, delegating to a qualified constructor is a reasonable precaution – but you must choose wisely. As Justice Martin of the SCC noted, an owner might be found to have taken every reasonable precaution “because the owner decided to delegate control of the project and responsibility for workplace safety to a more experienced constructor.” (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology). That delegation, however, must be to someone actually capable of doing the job right.

5. Formalize Roles and Communications: At the project kickoff, ensure that everyone understands who the constructor is and what the owner’s involvement will be. The constructor should be leading all safety coordination. If the owner has any representatives on site (project managers, inspectors, engineers), clarify that their role is oversight/quality control only, not directing work. It can be helpful to document this in an internal charter or in the contract kickoff meeting minutes. Also establish a protocol for issue escalation: for example, “Owner’s site rep will communicate safety or quality concerns to Constructor’s site superintendent or project manager, who will address them promptly.” This prevents confusion on the ground and minimizes the chance that an owner’s instruction could be misinterpreted as taking control. Keep records of all such communications, as they could become evidence of either taking control or exercising due diligence, depending on how they were handled. The goal is that any outsider examining the project would clearly see the constructor at the helm of safety management, with the owner in a monitoring role. All optics should reinforce that the contractor is the constructor (Worklaw® Network - Ontario: The Fine Line between “Owner” and “Constructor”).

6. Limit On-Site Presence of Owner’s Staff (and Train Them): Consider how many of your own employees truly need to be on the project site. The more staff you station there, the greater the chance you’ll be seen as participating in the project execution (and each of those staff means you are an employer with workers on site). Only assign those necessary for oversight. When you do send owner personnel (be it engineers, inspectors, or managers), ensure they are properly trained in construction safety and your internal protocols. They should attend the constructor’s safety orientation and abide by all site rules (PPE, signing in, etc.) just like any worker. From a liability standpoint, having your employees on site means you must also protect their health and safety. Under OHSA section 25(2)(h) – the “general duty” clause – every employer must take reasonable precautions for the protection of their workers. This implies you should verify the site is safe before sending your staff. So, coordinate with the constructor: for example, require that any owner visits are escorted or that certain high-risk areas are off-limits to non-constructor personnel unless cleared. If your employees will perform any work or testing on site, treat that as a separate work activity that must be integrated into the constructor’s safety plan. Essentially, the owner’s workers should be subject to the constructor’s safety management, and the owner should confirm that’s happening. Never allow your staff to perform ad-hoc work on the project without informing the constructor. By respecting the constructor’s control while safeguarding your employees, you fulfill your overlapping employer duty without blurring the lines of who controls what.

7. Know the Key Safety Requirements of O. Reg. 213/91 and Ensure They’re Being Met: The Construction Projects regulation (O. Reg. 213/91) is extensive, but owners should be aware of the major “prescribed” measures that apply to their project. This includes things like: proper fencing to secure the site (often 1.8m fencing for public protection), safe excavation procedures (trenches shored or sloped as required), fall protection for work above 3 metres, having a competent supervisor on site, utility locates, appropriate traffic control (signallers or paid duty officers for work on roadways), and mandatory notices (e.g. Notice of Project filings, notifications for use of certain equipment or occurrences of accidents). While the constructor is charged with day-to-day compliance, the owner-as-employer has a duty to “ensure” these measures are carried out (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology). In practical terms, this means the owner should periodically verify that the constructor has done things like filed the Notice of Project, put up required warning signs, and implemented site-specific safety plans. One useful tool is a project safety checklist for owners, used during site visits or meetings, covering the main regulatory requirements. By checking against this list, the owner’s rep can have informed discussions with the constructor (“Have all workers received fall protection training as required? Is our trench over 1.2m deep certified by an engineer as per the regulation?”). This not only helps catch any gaps early but also shows that the owner took steps to ensure compliance. Remember, an owner can be found liable if a critical regulation is breached on their project and they did nothing to confirm the constructor was handling it. Conversely, if you can show you actively inquired about and pushed for all safety measures to be in place, you bolster your due diligence position significantly.

8. Document Everything: Good record-keeping is a cornerstone of legal defense. Owners and their safety advisors should keep a detailed record of all safety-related efforts: contractor selection notes, contract clauses on safety, meeting minutes, inspection reports, emails/letters to the constructor about issues, responses and corrective actions, etc. If an incident occurs, these documents will be crucial. They can demonstrate that the owner had a system in place to prevent incidents (which might prevent charges in the first place, or help in court later). For example, if the Ministry of Labour investigates a serious incident, an owner who can immediately produce proof that they hired a vetted constructor, communicated all known hazards to that constructor (like designated substances or site-specific risks), and regularly checked that the constructor was meeting its safety obligations, will be in a far better position than one who has no records or who simply “assumed” things were fine. In a prosecution, establishing a due diligence defense requires showing the court evidence of the reasonable steps you took. Contemporaneous documents carry a lot of weight in this analysis. They can show the mindset and actions of the owner before the incident, which is much more convincing than after-the-fact claims. As a rule of thumb: if it wasn’t documented, it’s as if it didn’t happen.

9. Be Prepared with a Response Plan if Something Goes Wrong: Despite best efforts, accidents can happen. Owners should have a plan for what to do if a serious incident or safety issue arises. This includes clear communication channels with the constructor (who notifies the Ministry of Labour, who investigates internally, etc.), and legal counsel contacts if needed. If an incident exposes a significant safety lapse, the owner may need to revisit whether the constructor is meeting its obligations. In extreme cases, the owner might have to exercise its right to step in or even replace the constructor to mitigate ongoing danger – but doing so would likely transfer constructor duties to the owner, so it must be a last resort. This kind of situation is delicate and requires legal guidance. The best scenario is not to reach that point by proactively managing the preceding steps. But having a plan ensures that if the worst happens, the owner’s team can respond in a way that continues to emphasize safety and compliance (which will again be looked at in any legal aftermath). For instance, an owner should not ignore a stop-work order or failed safety audit; they should actively engage in the solution, again through the constructor when possible.

By following these practices, owners and their advisors can greatly reduce the risk of being deemed the constructor inadvertently, and also strengthen their ability to defend against any OHSA charges as an employer. The Supreme Court has effectively put owners on notice that “contracting out the role of Constructor does not mean contracting out of safety responsibility.” (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology). However, the Court also provided a roadmap for owners to protect themselves: the due diligence “safety valve” will excuse an owner from liability if they can prove they took all reasonable steps in the circumstances (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology). The factors a court will consider include the owner’s degree of control, whether they delegated to a competent constructor, how they evaluated the constructor’s safety ability, and how effectively they monitored the constructor’s work for safety compliance (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology). Each of the tips above is aimed at covering these very factors. In sum, if you choose a capable constructor, clearly hand them the reins, and diligently monitor the project’s safety (intervening only through appropriate channels), you stand a very good chance of avoiding legal fallout even if an accident occurs.

Conclusion

Ontario’s legal landscape around construction safety has evolved – owners and senior managers can no longer assume that liability rests solely with the general contractor. The City of Sudbury case has made it clear that everyone with a role in a construction project bears some responsibility for safety, and failing to recognize that can have costly consequences. Business owners must approach construction projects with eyes open to their potential duties as constructors or employers. The OHSA and Construction Projects regulation impose rigorous standards, but with careful planning and due diligence, it is possible to meet those standards without falling into the trap of unintended liability.

For owners and constructors alike, the mantra should be: clarity, communication, and compliance. Define who is the constructor from the outset and ensure all parties understand their roles. Communicate regularly about safety expectations and issues. And keep the project in compliance with regulatory requirements by leveraging the strengths of each party – the constructor’s on-site control and expertise, and the owner’s oversight and resources. By implementing the best practices outlined above, owners and workplace parties can foster safer construction projects and shield themselves from legal repercussions. The law ultimately wants to encourage proactive safety management; those who demonstrate it will find the law to be an ally, not an adversary. As the Sudbury case illustrates, due diligence is not just a legal defense – it’s a sound business practice that protects both people and the bottom line (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology).

Sources:

• Occupational Health and Safety Act, R.S.O. 1990, c. O.1, particularly sections 1(1) (“constructor” and “employer” definitions), 1(3), 23, 25 (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology) (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology) ( My Responsibilities as a Contractor ) (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology).

• Ontario Regulation 213/91 (Construction Projects), which prescribes specific safety measures (e.g. signallers, fencing, notices) that constructors and employers must ensure (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology) (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology).

• R. v. Greater Sudbury (City), 2023 SCC 28 – Supreme Court of Canada decision (split 4-4) confirming that a project owner can be an “employer” under OHSA, with overlapping safety duties (Court rules in City of Sudbury's favour on issue of due diligence | Canadian Occupational Safety) (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology).

• R. v. Greater Sudbury (City), 2024 ONSC 3959 – Ontario Superior Court decision affirming the City’s due diligence in hiring and monitoring a competent constructor (Court rules in City of Sudbury's favour on issue of due diligence | Canadian Occupational Safety) (Court rules in City of Sudbury's favour on issue of due diligence | Canadian Occupational Safety).

• Analysis and commentary: Stringer LLP (Conlin), “Ontario: The Fine Line between Owner and Constructor” (Worklaw® Network - Ontario: The Fine Line between “Owner” and “Constructor”) (Worklaw® Network - Ontario: The Fine Line between “Owner” and “Constructor”); Canadian Occupational Safety magazine (Court rules in City of Sudbury's favour on issue of due diligence | Canadian Occupational Safety) (Court rules in City of Sudbury's favour on issue of due diligence | Canadian Occupational Safety); Miller Thomson LLP on the SCC ruling (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology) (Supreme Court confirms that construction project owners can be held liable as “employers” under Ontario’s OHSA - Lexology); IHSA article on SCC decision ( Defining roles on the jobsite ) ( Defining roles on the jobsite ); Ontario Association of Architects FAQ on owners vs constructors ( Practice Advisory Knowledge Base - FAQ.05 OHSA - When is an Owner a Constructor? ).