A New Year's Eve party invitation from a Redlands councillor inadvertently shared personal details of hundreds of residents, and their details of correspondence with council.
A spreadsheet attached to an email sent by division 8 councillor Tracey Huges contained names, addresses, phone numbers and details of dealings with Redland City Council.
It went to close to 300 people living in Cr Huges' ward on December 7.
But some of those whose details were shared were only notified by email of the mistake after 5.30pm on December 20.
Council notified the 297 people who received the email on December 9.
That email, sent by acting Governance Services manager Kristine Viller, said that information had been disclosed to third parties.
"The content of the information is specific to each individual, however it does not comprise more than general contact information and a brief description of your interaction with council regarding matters in Division 8, if such matters occurred," it read.
"On behalf of council, I sincerely apologise and regret this situation has occurred. Council is committed to protecting its personal information holdings and an individual's right to privacy, and, unfortunately, this has not occurred."
A man who spoke to the Bulletin was angry about receiving the email.
A woman, who did not want to be named, said she was angry she was unable to contact council over the weekend to inquire about the issue.
"I was shocked, confused, angry and frustrated at the fact I had to wait until Monday to get any further information," she said.
"The initial email was quite vague on the specifics of what information had been breached.
"Councillor Huges has not responded privately to messages or publicly apologised for the stress this has caused people, myself included."
She questioned the timing of the apology letter sent on the Friday afternoon.
"It's clear from the start the way it's being handled from that first email at 5.40pm on Friday evening that council are hoping it gets overlooked by many people, therefore sweeping it under the rug," she said.
"Since when do you receive such an important email after hours on a Friday, the Friday before Christmas at that?"
"Sorry is not good enough," she said.
Cr Huges said she regretted the error.
"On sending out a New Year's Eve invitation, I inadvertently attached my contact list, not the invitation," she said in a statement.
"I collated my contact list from residents contacting me personally seeking assistance with an issue and I stored the list to ensure I was able to follow up and advocate for them.
"I am deeply distressed and sincerely apologise to all residents."
A council spokesman said the incident had been reported to the Office of the Information Commissioner and the Office of the Independent Assessor.
"Council contacted both the OIC and OIA on December 9, the same day it became aware of the alleged privacy breach by Cr Huges - and reported the matter officially over the following days," the spokesman said.
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