British Columbia said Tuesday it was preparing a lawsuit against OpenAI over the company's failure to report violent ChatGPT activity by the person who committed a mass school shooting in the western Canadian province.

OpenAI had banned an account linked to Jesse Van Rootselaar in June 2025, months before the 18-year-old transgender woman killed eight people at her home and a school in the tiny mining town of Tumbler Ridge.

Canadian families impacted by the February shooting have already filed lawsuits against the US tech giant in a California court.

British Columbia said Tuesday it was preparing a separate case, in coordination with the families, and had retained lawyers both in Canada and California.

Provincial Attorney General Niki Sharma told reporters BC wanted to "hold OpenAI and its decision-makers accountable for their failure to notify law enforcement of the violent prompts made on its ChatGPT platform by the perpetrator prior to the tragedy in Tumbler Ridge."

"British Columbia has never shied away from taking on powerful corporations when their actions cause harm to people and communities," she added.

She cautioned the legal process will "take time," but said funds derived from a lawsuit would help Tumbler Ridge rebuild, including supporting the construction of a new school.

The province wants to use the courts to "ensure that British Columbians are not left bearing the costs of corporate wrongdoings."

Asked for comment on the province's legal plans, OpenAI said it has "already strengthened our safeguards, including improving how ChatGPT responds to signs of distress."

"We have a zero-tolerance policy for using our tools to assist in committing violence," a company spokesperson added in a statement.

- Sam Altman apology -

In April, OpenAI CEO Sam Altman apologized to residents of Tumbler Ridge, saying in a public letter that he was "deeply sorry that we did not alert law enforcement to the account that was banned in June."

OpenAI has said that it did not report Van Rootselaar's account at the time of the suspension because it saw no evidence of an imminent attack.

But it has also said that under updated security guidelines imposed after June 2025, the account would have been reported to police.

Lawyers for the families suing the company in a US federal court in California have alleged that OpenAI chose to stay silent about Van Rootselaar's account because "reporting one case would mean reporting thousands."

Their lawsuit also claims that when an account is shut down for dangerous behavior, OpenAI instructs the individual on how to resume usage, including tips on how to circumvent the 30-day suspension period.

The chief AI officer at Ontario's Western Univerity, Mark Daley, told AFP Tuesday that "Tumbler Ridge shows what happens when one private company knows about an imminent threat that no police force can see and decides not to act."

"The lesson isn't that OpenAI is uniquely bad. It's that no single company, however well-intentioned, should be the only one holding that kind of knowledge," he said.

Van Rootselaar killed her mother and brother at the family's home before heading to the local secondary school, where she shot dead five children and a teacher.

She died of a self-inflicted gunshot wound after police entered the building.