‘The existence alone of a pre-existing condition does not automatically open the door to cost relief,' says lawyer
A recent decision from the Workplace Safety and Insurance Appeals Tribunal (WSIAT) reaffirms the strict evidentiary requirements employers must meet to qualify for cost relief under Ontario’s Second Injury and Enhancement Fund (SIEF).
The SIEF’s core intent is to assist employers financially when an employee’s pre-existing condition contributes to the severity or duration of a workplace injury; according to Shannon Sproule, lawyer with Turnpenny Milne in Toronto.
“The purpose of it is actually to encourage employers to hire workers with disabilities.”
The Tribunal’s decision, Decision No. 1514/24, 2025 ONWSIAT 83, however, demonstrates that the bar remains high for employers seeking this form of relief — particularly when evidence is lacking or the connection between a prior condition and the injury is weak.
Documentation must prove more than vulnerability
In the WSIAT appeal ruling, it was detailed how an employee of a grocery store, a seafood manager, had slipped and fell on meat and fat on the floor while walking past the meat counter.
“The worker had pain in her neck, right shoulder, right arm, leg, and middle finger. Her middle finger suffered a bony avulsion fracture…The Board granted entitlement for right forearm soft tissue injuries, right middle finger fracture, right shoulder strain/sprain, and right full thickness supraspinatus tendon tear,” the decision stated.
In its appeal, the employer pointed to the worker’s earlier right shoulder injuries and mild degenerative changes to argue for a 75%–90% reduction in costs under the SIEF. Specifically, it cited a history of right shoulder injuries spanning more than two decades, including a motor vehicle accident from over 20 years ago, workplace injuries in 2006 and 2011, and a 2018 non-compensable rotator cuff injury that was noted as fully resolved.
They also pointed to medical imaging that showed mild degenerative changes in the worker’s shoulder following the 2019 workplace fall. But the Tribunal found there was no medical evidence to connect this occurrences to the employee’s current injury recovery.
Stephanie Savoni, chair of Hicks Morley’s Workplace Safety and Insurance Practice Group, explains the high bar.
“The entry point is that the existence alone of a pre-existing condition does not automatically open the door to cost relief under this second injury and enhancement fund,” she says.
“There has to be medical evidence that that pre-existing condition either contributed to the accident itself or prolonged or enhanced, so made recovery longer or made the injury worse. So there has to be a direct link.”
Submissions not evidence in SIEF applications
Sproule emphasizes that this was the crux of this SIEF analysis; the adjudicator in the decision clarified that vulnerability alone is not enough. There must be a demonstrated impact on the actual course of recovery.
“The medical documentation, while it showed that there had been previous medical issues and a motor vehicle accident, those were quite remote,” Sproule says.
“What they didn't prove is that it had a significant role in causing the workplace accident or injury, or that the pre-existing condition actually prolonged or enhanced the recovery … it had to convince the adjudicator, it had to prove that it's more likely than not.”
Although the employer claimed the worker had been previously accommodated for shoulder limitations, there was no documentation to support that. The decision emphasized that “submissions aren’t evidence” and reiterated that a successful SIEF claim must include clear medical proof that a pre-existing condition actively contributed to a prolonged or more severe recovery — a threshold this employer did not meet.
SIEF applications: why timing and strategy matter
Sproule suggests that employers need to plan for potential cost relief as early as possible: “It's essentially diluting your liability and reducing what you have to pay. So it would make sense to do that at the outset as an employer, when you're initially responding to the employee's claim.”
Savoni agrees, adding that timing matters because applying for SIEF relief funding too early can have pitfalls.
“Sometimes employers will want to pursue cost relief right away,” she says. "But it's probably much too early. It is much too early to conclude that this injury has been prolonged and enhanced.”
However, she adds, “an employer should certainly have it on their radar.”
The Tribunal in 1514/24 made it clear that hindsight alone won’t support a claim – employers must not only monitor the recovery but also be proactive in requesting access to documentation.
“If you think there's a pre-existing condition, they won’t even render a decision,” Savoni says. “If an employer just says, We think this person had a pre-existing condition, there has to be something for the WSIB to go on to take a look at it, so that piece would be in the employer's hands.”
Savoni also points out that some pre-existing conditions may only emerge as a result of a workplace accident – for example, a narrowed spine discovered via a post-fall MRI scan.
Determining the extent of SIEF cost relief
Once the WSIB establishes that the threshold is met — that a pre-existing condition did in fact contribute to the workplace injury or prolonged recovery — it determines how much cost relief is appropriate.
This step involves a formal two-variable analysis, Savoni outlines.
“They look at the medical significance of the pre-existing condition, and that’s minor, moderate or major,” she explains.
“And it’s assessed in terms of the extent that it would make a worker more liable to develop a disability of greater severity than someone without that condition.”
The second variable is the severity of the accident, Savoni says. “So was it minor, moderate or major, this pre-existing condition? And they use medical evidence to assess that. The second variable that they look at is the severity of the accident.”
Based on these factors, the WSIB refers to a chart to assign cost relief percentages, ranging from 0% to 100%.
How mental stress and complexity affect SIEF decisions
Mental stress claims further complicate the application of SIEF; Sproule notes that psychological disabilities are already difficult to prove in Ontario, and the same evidentiary bar applies.
“This will be a complex one – it's a much more nuanced and complex analysis when it's psychological versus physical.”
Savoni confirms that mental stress claims are also covered by the SIEF policy: “In Ontario, there is potential entitlement for what we call mental stress injuries, and so this policy also applies for mental stress injuries in much the same way,” she says.
“You could see a medical opinion from a doctor saying, “We've diagnosed the worker with ADHD, which is unrelated to work, and we do believe that is enhancing and prolonging the condition and is a barrier to recovery. So you could certainly make the argument if the diagnosis is not already in the medical file.”
Savoni adds that while reaching SIEF evidentiary requirements for mental health injury may be difficult to achieve for employers, in some situations, it might be possible: “There’s evidence that if somebody has suffered childhood trauma and has been diagnosed with PTSD as a result, that can make the road to recovery much more difficult.”
Strategy and persistence are key
While employers often file for cost relief, success depends on the strength of evidence, says Savoni.
“We do see a lot of decisions ... there is pre-existing, but the medical evidence is lacking. But yes, we are successful in getting cost relief in a lot of claims as well.”
Savoni stresses that the most important consideration is documentation. Whatever the nature of the pre-existing condition being claimed, the message remains clear: a successful SIEF claim must prove more than correlation – it must prove causation or direct impact on recovery, and it must do so with robust medical evidence.
“This finding just can't be based on arguments or assertions made by the employer,” she stresses.
“When we talk about medical evidence, we're talking about medical reports, evaluations that provide an opinion from that treating practitioner that the pre-existing condition has enhanced or prolonged an injury or illness in the recovery.”
