OTTAWA -- Coun. Tim Tierney has admitted he breached council’s code of conduct by forwarding a confidential memo about the city’s lawsuit over the Rideau Street sinkhole to a reporter.

On May 27, council voted 18 to 6 to ask the city’s integrity commissioner to investigate whether a member of council released a memo on the $361 million lawsuit launched by the city. Tierney was one of the councillors who voted in favour of the integrity commissioner's investigation.

During Wednesday's council meeting, Tierney told his council colleagues that he "inadvertently" included the confidential memo in a bundle of documents he sent to a journalist on an unrelated issue.

"I need to take the opportunity to publicly advise my council colleagues, city staff and residents of Ward 11 Beacon Hill-Cyrville that I was the person who sent the confidential memo dated May 10, 2021 entitled "Claims Related to Builders Risk Policy Following the Sinkhole Event" to a member of the media and for the inappropriate action I'm truly sorry and sincerely apologize," said Tierney.

"I want council to understand that I take full responsibility, but I also want them to know that it was due to the careless on my part and it was not an intentional breach of council confidentiality."

Tierney told council sending the memo was a "mistake", and promised to be "much, much more careful in the future" when emailing documents.

"I will never breach the council's confidentiality requirements again. I once again apologize for this mistake," said Tierney.

Tierney said he discovered he forwarded the memo to the journalist after council asked the integrity commissioner to investigate the memo's leak.

Council unanimously accepted a motion to accept Tierney's apology and recommend the integrity commissioner stop the investigation.

Mayor Jim Watson told reporters after Wednesday's council meeting that his office was informed on Monday that Tierney had leaked the memo to the media.

"Coun. Tierney is remorseful, he's admitted he made a mistake and an error and he's apologized, and that was accepted today by council," said Watson.

On Twitter, Coun. Shawn Menard said he doesn't think there should be any punishment, but wondered what the reaction would be if other councillors leaked the memo.

"Imagine if it was me or Catherine McKenney or other independent councillors? Table pounding about confidentiality and taxpayer dollars would not stop," said Menard.