Executive Summary: Key Legal and Evidentiary Issues

• Sufficiency of proof of alleged professional errors by the accountant in preparing the 2019 and 2020 tax returns
• Characterization of the accountant’s obligation as an obligation of means under a contract of services, not an obligation of result
• Impact of the client’s own failure to review and verify draft tax returns before signing and filing them
• Absence of expert evidence or detailed financial analysis to link the alleged mistakes to the tax reassessments and claimed damages
• Credibility assessment between the taxpayer and the accountant regarding the timing of transmission and review of the draft returns
• Causation between any potential error and the tax authorities’ reassessments, including penalties, and whether these amounts are fully recoverable as damages

Facts of the case

Stéphane Boisvert brought a small claims action before the Court of Québec, Civil Chamber, Small Claims Division, against his accountant, Daniel Lasnier, and the accounting corporation Daniel Lasnier CPA inc. He sought a total of $11,972.98. Of this, $8,972.98 represented amounts reassessed and newly cotised by Revenu Québec and the Canada Revenue Agency, including penalties, following a tax audit targeting his 2019 and 2020 tax years. The remaining $3,000 was claimed as compensation for trouble and inconvenience allegedly caused by the situation.
Mr. Boisvert had retained Mr. Lasnier and his firm to prepare and file his income tax returns for several years, from 2016 to 2021. According to Mr. Boisvert, the process followed each year was the same: he sent what he considered to be the relevant financial and tax information to the accountant ahead of the deadline, the accountant prepared draft returns based on that information, and these drafts were then sent to him for review and approval before filing with the tax authorities.
In 2022, Mr. Boisvert was notified that Revenu Québec had initiated a tax audit concerning his 2019 and 2020 tax years. The audit process lasted about seven months and led to new tax assessments from both Revenu Québec and the Canada Revenue Agency. Mr. Boisvert alleged that those new assessments, and the resulting additional tax and penalties, flowed directly from errors made by the defendants in preparing his returns for those two years.

Alleged professional errors and complaints

Mr. Boisvert identified three main alleged errors. First, he claimed that the accountant failed to declare a $16,000 expense in relation to the sale of a property in 2020. Second, he argued that there was an unjustified increase in the percentage of personal use allocated to a revenue-generating property: the personal-use proportion was allegedly changed from 40% in 2018 and 2019 to 50% in 2020, without a valid explanation. Third, he maintained that he received incorrect advice about deducting expenses connected to a property rented to a related person, asserting that he had been told such deductions would be acceptable.
Despite these allegations, Mr. Boisvert was unable to clearly explain in court the detailed tax and monetary impact of each alleged error. He described, in broad terms, his understanding of the possible mistakes and their consequences, but he did not break down how each specific item translated into the assessed amounts, penalties, or longer-term fiscal effects.
Mr. Boisvert chose not to retain an expert, such as another accountant or tax specialist, to analyze the tax file, reconstruct the computations, or explain the exact nature and impact of the alleged errors. This was despite the fact that the possibility of retaining such an expert had been raised and brought to his attention during case management, before the matter was placed on the trial roll. The limited documents he filed, including some tax slips and a letter from the Ordre des comptables professionnels agréés du Québec, did not address the specific alleged errors in the 2019 and 2020 returns or establish proof of fault.

Defence position and contractual framework

The defendants denied any professional fault and maintained that they had prepared the tax returns in accordance with professional standards—the “rules of the art.” They stressed that they relied on the information provided by Mr. Boisvert and emphasized that it was his responsibility to review the draft returns before authorizing their filing.
Legally, the court characterized the relationship between Mr. Boisvert and the accountant as a contract of services under article 2098 of the Civil Code of Québec. This type of contract gives rise to obligations that include acting with prudence, diligence, and in accordance with professional standards. For an accountant, the obligation is one of means, not result: the professional must use appropriate care and competence but does not guarantee a particular tax outcome or the absence of any future audit or reassessment.
The court also referred to general contractual liability provisions in the Civil Code of Québec. Under these rules, a party who fails to honour a contractual obligation is responsible for the bodily, moral, or material prejudice caused to the other contracting party, but only for damages that were foreseeable at the time of contracting and that constitute an immediate and direct consequence of the breach. These principles framed the analysis of whether any proven error by the accountant would justify an award of the additional tax and penalties as damages.

Client’s duty to review and evidentiary shortcomings

A crucial factual and legal point in the court’s reasoning was the taxpayer’s own duty to review and verify the tax returns he signs. The court found that Mr. Boisvert did not take the time to properly review the draft returns before approving them. He admitted that, due to his numerous family and professional commitments and his trust in the accountant, he limited himself to looking at the bottom line numbers rather than checking the content of the returns in any detail.
Mr. Boisvert also claimed that the drafts were often sent to him at the last minute, leaving him no real opportunity to review them. The court rejected this allegation as not credible. The accountant testified that he always allowed a reasonable period for clients to review and sign, except in exceptional circumstances, which did not exist here. The judge considered it unlikely that an experienced taxpayer would repeatedly receive nearly late drafts over several years, feel pressured every time, and nonetheless continue to use the same accountant without raising the issue or changing providers.
This finding led the court to conclude that Mr. Boisvert had simply neglected to devote the minimal time necessary to review his returns, despite bearing ultimate responsibility to the tax authorities for their accuracy and completeness. The court found that even if some errors had slipped into the drafts, a minimal review by Mr. Boisvert would likely have caught the issues he described concerning the property sale expense and the change in personal-use percentage before filing, or allowed him to seek corrections afterwards.

Assessment of alleged advice and causation

Regarding the complaint about advice on expenses related to a property rented to a related person, the accountant maintained that he had never guaranteed that such expenses would be accepted by the tax authorities. He also stated that he had not even been aware that the property was occupied by a related individual. Faced with conflicting testimony and no documentary or expert evidence to corroborate Mr. Boisvert’s version, the court preferred the accountant’s explanation or, at minimum, found that the client had not discharged his burden of proof.
Overall, the judge emphasized that Mr. Boisvert bore the burden of proving the specific errors, the resulting tax consequences, and the causal link between any professional fault and the reassessments and penalties. Without a detailed breakdown of the alleged mistakes, without expert analysis, and with only sparse supporting documentation, the allegations remained at the level of hypotheses. The court concluded that there was insufficient clear and convincing evidence to establish a professional fault by the accountant or to quantify any recoverable damages.

Ruling and outcome

In light of the contractual framework, the professional obligations of the accountant, the taxpayer’s own duty to verify his returns, and the evidentiary gaps in the plaintiff’s case, the Court of Québec rejected Mr. Boisvert’s claim in its entirety. The judge held that the alleged errors had not been proven and that, even if some discrepancies existed, Mr. Boisvert had failed to demonstrate a direct, immediate, and compensable loss attributable to a professional fault by the defendants.
As a result, the action for $11,972.98—comprising the reassessed tax, penalties, and an additional claim for inconvenience—was dismissed. The court instead ordered Mr. Boisvert to pay the defendants’ legal costs related to their joint contestation in the fixed amount of $364. In practical terms, the successful parties were the defendants, Daniel Lasnier and Daniel Lasnier CPA inc., in whose favour the court granted a total monetary award of $364 in costs.