UPDATED: Tax Court judge slams AI-generated fake case law in CRA dispute
https://www.westernstandard.news/news/tax-court-judge-slams-ai-generated-fake-case-law-in-cra-dispute/74752
A Tax Court judge has issued a sharp warning against the use of artificial intelligence-generated legal citations after a self-represented taxpayer challenged the Canada Revenue Agency (CRA) using cases that did not exist.
According to Blacklock’s Reporter, Justice Michael Ezri dismissed submissions in Forrest v. His Majesty after determining they relied on fabricated case law that was likely produced by an AI chatbot.
“AI is no substitute for real lawyering,” Ezri wrote in his ruling. “I therefore placed no weight on either the original submissions or the replacement submissions.”
The judge said litigants, including those representing themselves, remain responsible for ensuring any authorities they cite are legitimate and that legal arguments are based on their own analysis.
“However this does not excuse the appellant or any self-represented litigant from their obligation to make sure the cases they cite are real and that the analysis is their own,” wrote Ezri. “The cases may be fake but the cost consequences of filing such nonsense are real.”
The comments stemmed from May 29 court filings in which a self-represented taxpayer cited two fictitious cases in an attempt to support a challenge against the CRA.
The ruling comes amid growing concern over the use of AI-generated legal research in Canadian courts.
A March 27 commentary by Tom Macintosh Zheng, a Toronto-based lawyer and co-founder of Courtready.ca, found that self-represented litigants were the most common source of fake legal citations appearing before courts and tribunals."
According to Zheng, who maintains a Canadian database tracking AI misuse in Canadian courts, the problem is growing rapidly.
As of July 5, 2026, Canadian courts and tribunals have identified at least 180 instances in which parties filed non-existent case law in legal proceedings, across 55 courts and tribunals nationwide.
The database recorded seven cases in 2024, 91 in 2025, and 82 already in the first half of 2026.
“For many self-represented Canadians AI may be their only realistic and cost-effective means of conducting legal research,” Zheng's report stated.
The report, titled The Rise Of AI-Hallucinated Case Law In Canadian Courts And Tribunals, warns the problem is likely more widespread than the documented figures suggest.
“The figures represented in this study represent a conservative floor, not a ceiling,” Zheng wrote.
“The methodology captures only those cases where an adjudicator detected and remarked upon a fictitious citation in a published decision. For every fictitious citation that a court catches, others may pass through.”
The study also found lawyers were responsible for 24 of the 132 documented cases involving “hallucinated” case law.
Researchers said Ontario recorded the highest number of decisions involving fake citations, followed by British Columbia, the federal jurisdiction, Quebec, Alberta, Saskatchewan and New Brunswick.
The concerns have already led to disciplinary action within the legal profession.
On June 12, the Law Society of Ontario ordered a Toronto lawyer to pay $31,150 for what it described as the “negligent and irresponsible use of artificial intelligence” in court filings.
In Mazaheri v. Law Society, the lawyer — whose licence had been suspended in 2024 — submitted materials generated with the assistance of AI that contained references to non-existent court decisions, regulators found.