COURT OF APPEAL FOR ONTARIO
Huscroft, Dawe and Wilson JJ.A.
BETWEEN
Bonnie Bradley
Plaintiff (Respondent)
and
Dr. Richard Wang* and Clinic Management and Technical Services
Defendants (Appellant*)
Kosta Kalogiros, Aya Schechner and Rudra Krishnan, for the appellant
John J. Adair, Emily Vaillancourt, Warren WhiteKnight and Casey Dorey, for the respondent
Heard: June 1, 2026
On appeal from the judgment of Justice Mary E. Vallee of the Superior Court of Justice, dated April 29, 2025, with reasons reported at 2025 ONSC 2267.
REASONS FOR DECISION
[1] The appellant, Dr. Richard Wang, administered a tetanus vaccine to the respondent, Bonnie Bradley, following which, Ms. Bradley experienced debilitating pain in and around the injection site and developed what is known as a “frozen shoulder”, which she said prevented her from working. Ms. Bradley brought an action against Dr. Wang, alleging negligence in the manner in which he administered the vaccine. The trial judge found that Dr. Wang was negligent and that his negligence caused Ms. Bradley’s damages, including loss of income and pension loss.
[2] Dr. Wang raises three grounds of appeal, arguing that the trial judge erred (1) in her analysis of the standard of care, by failing to apply the correct analytical framework when assessing the credibility and reliability of the parties’ evidence; (2) in her analysis of causation, by failing to apply the “but for” test; and (3) in her assessment of damages, by failing to address mitigation. We do not accept that the trial judge made the alleged errors and dismiss the appeal.
A. Background Facts
[3] On December 1, 2015, Ms. Bradley attended her family doctor’s office for a tetanus vaccination. Dr. Wang, a first-year family medicine resident who was being supervised by Ms. Bradley’s family doctor, administered the vaccine. Upon injection, Ms. Bradley testified that she experienced severe pain at the injection site. She immediately looked at the needle, which was still in her arm, and observed that it was not in the right place. It was too high up and too far towards the front of her arm. As a registered nurse who had administered many vaccinations herself, she was familiar with the correct location for injection.
[4] In the days, weeks, and months following the injection, Ms. Bradley experienced debilitating and unremitting pain in her arm and shoulder, as well as a restriction in movement. She tried to work in her job as an emergency department nurse, but could not do so. A little over a week after the vaccination, she stopped going to work entirely and has never returned to any sort of employment. Specialists who assessed Ms. Bradley opined that she had experienced an adverse inflammatory response to the vaccination and had developed adhesive capsulitis (also known as a frozen shoulder).
[5] At trial, the parties agreed that if Dr. Wang had administered the vaccine in the location Ms. Bradley described he had breached the standard of care. Dr. Wang, unsurprisingly, could not recall the specifics of the appointment. His notes from the appointment also did not describe the precise location of the injection. He denied, however, that he would administer a vaccine in the area described by Ms. Bradley, relying on his usual practice. The trial judge accepted Ms. Bradley’s evidence as to where the needle had been inserted, rejecting numerous challenges by Dr. Wang to her credibility and reliability. She favoured Ms. Bradley’s direct eye-witness evidence over Dr. Wang’s evidence of his usual practice, and accordingly found that Dr. Wang had breached the standard of care.
[6] Dr. Wang argued that, even if he had breached the standard of care, his negligence did not cause Ms. Bradley’s injuries. He relied on expert evidence to the effect that adverse reactions to properly-administered vaccines, while rare, do occur. The trial judge rejected this argument, finding that but for the negligent administration of the vaccine, Ms. Bradley would not have had the inflammatory reaction that she did. Instead, she likely would have had no reaction, consistent with her history of receiving tetanus vaccinations.
[7] Finally, the trial judge found that, as a result of her injury, Ms. Bradley was incapable of returning to her job as an emergency department nurse. She rejected evidence led by Dr. Wang that there were other suitable positions that Ms. Bradley could have taken instead. She awarded damages for loss of income in the sum of $931,585 and for pension loss in the sum of $361,600.
B. Analysis
a. Standard of Care
[8] Dr. Wang submits that the trial judge erred in her approach to the assessment of the credibility and reliability of the parties’ evidence. He asserts that she failed to effectively analyze Dr. Wang’s evidence and did not address material inconsistences in Ms. Bradley’s testimony. At minimum, he says the trial judge’s reasons on credibility are insufficient and do not allow for meaningful appellate review. We disagree.
[9] It is well established that a trial judge’s reasons must be read functionally and as a whole, in light of the evidence and submissions, and with an understanding that it may be difficult to articulate why a particular witness was believed or disbelieved: Farej v. Fellows, 2022 ONCA 254, at paras. 45-50, leave to appeal refused, [2022] S.C.C.A. No. 180; Monk v. Farmers’ Mutual Insurance Company (Lindsay), 2019 ONCA 616, 92 B.L.R. (5th) 1, at para. 64, leave to appeal refused, [2019] S.C.C.A. No. 384. Moreover, a trial judge is under no obligation to refer to every piece of evidence, address every argument made by the parties, or resolve every alleged inconsistency in a witness’s testimony: Liu v. Huang, 2020 ONCA 450, at para. 18.
[10] As long as a trial judge has engaged in a reasoned assessment of a witness’s testimony, addressing the key challenges to credibility and reliability raised before them, their decision to believe or disbelieve all or any part of that witness’s testimony will be owed significant deference: Housen v. Nikolaisen, 2002 SCC 33, [2002] 2 SCR 235, at para. 72.
[11] Credibility was a significant issue at trial. The parties had agreed that whether the standard of care had been breached depended entirely on whether Ms. Bradley’s evidence as to the location of injection was accepted. Dr. Wang’s defence involved a series of attacks to her credibility and reliability. He argued, among other things, that Ms. Bradley had not had the opportunity to observe the insertion of the needle; that her evidence was inconsistent; and that she was an unreliable historian. The trial judge was well aware of the significance of the issue of Ms. Bradley’s credibility and reliability and carefully considered these challenges to her testimony before rejecting them. She then reasonably accepted Ms. Bradley’s direct eye-witness evidence over Dr. Wang’s evidence of his usual practice, as she was entitled to do. Her decision to believe Ms. Bradley is owed deference. There is no basis for this court to interfere with it.
b. Causation
[12] Dr. Wang submits that the trial judge failed to properly apply the “but for” test for causation. He argues that Ms. Bradley did not lead any evidence of what would have happened in the “but for” world. In the absence of any evidence on this point, Dr. Wang contends that the trial judge improperly relied on commonsense inferences and reasoned backwards from the mere fact of injury. We disagree.
[13] Ms. Bradley’s expert, Dr. David Ruggles, opined that it would be extremely unlikely for a patient to have experienced Ms. Bradley’s symptoms following a properly-administered vaccination. While he admitted that adverse reactions to vaccinations can occur, he testified that these occurrences are rare and that Ms. Bradley’s symptoms – involving immediate, severe, and unremitting pain – were inconsistent with those associated with a patient experiencing an abnormal immune response from a properly-administered vaccine. Moreover, there was evidence that Ms. Bradley had received tetanus vaccinations in the past without incident. Contrary to Dr. Wang’s submission, this was evidence of what might have occurred in the “but for” world. The trial judge made no reviewable error in relying on it and in coming to the common-sense conclusion that, but for the improper administration of the vaccine, Ms. Bradley likely would not have suffered the injury that she did.
c. Damages
[14] Dr. Wang submits that the trial judge erred in her assessment of damages, by failing to address the issue of mitigation. He notes that the word “mitigation” does not appear in her reasons despite the issue being raised before her. He also points out that the trial judge made no finding that Ms. Bradley made any efforts, let alone reasonable ones, to return to work. We reject this submission.
[15] Although the trial judge did not use the word “mitigation”, and it would have been preferable if she had done so, in substance, her reasons addressed the issue. The burden of proving the absence of mitigation rested on Dr. Wang who was required to prove both that Ms. Bradley failed to make reasonable efforts to mitigate and that mitigation was possible: Southcott Estates Inc. v. Toronto Catholic District School Board, 2012 SCC 51, [2012] 2 S.C.R. 675, at para. 24. Although the trial judge did not find that Ms. Bradley made reasonable efforts to mitigate her losses, she did address the second aspect of Dr. Wang’s burden. She accepted Dr. Ruggles’ testimony that Ms. Bradley would not be able to return to her work as an emergency department nurse and rejected evidence led by Dr. Wang that there were other suitable jobs that she could perform. These other jobs were all too far away from Ms. Bradley, who could not tolerate a commute of longer than 45 km due to her injury. While the distance between these jobs and Ms. Bradley’s home was largely due to her move from Courtice to Marmora in 2017, the trial judge found that this move was not unreasonable. The move from her Courtice home was for financial reasons, following the loss of her ability to work as an emergency department nurse, as she had prior to the incident. These findings, which are owed deference, were sufficient to dispose of Dr. Wang’s argument that Ms. Bradley had not mitigated her damages. Dr. Wang failed to prove that there were suitable jobs for Ms. Bradley in the area where she resides and thus that mitigation was possible.
C. Disposition
[16] The appeal is dismissed. Costs to the respondent in the agreed-upon amount of $50,000, all inclusive.
“Grant Huscroft J.A.”
“J. Dawe J.A.”
“D.A. Wilson J.A.”