Multiple privacy breaches involving more than 6000 people in the past year show "systemic issues" at the Inland Revenue Department, Labour says.
A release of documents under the Official Information Act shows 32 breaches involving 6300 individuals.
Labour revenue spokesman David Clark said the situation was "outrageous".
He believes that, including mass privacy breaches at the Accident Compensation Corporation and Work and Income, almost 16,000 people have had their personal details wrongly released.
"One privacy breach is too many . . . Something terribly wrong is going on at IRD," he said.
"[Revenue Minister] Peter Dunne is taking his eye off the ball."
More than 5000 Inland Revenue clients had not been told of the breach, he said.
The department alerted 679 clients because they were considered at risk of identity theft.
In March it was revealed ACC mistakenly released the names and details of 6500 clients, including 250 sensitive-claims clients who are victims of sexual abuse and violent crimes.
Privacy breaches at Work and Income have mounted after it was revealed earlier this month that a major security flaw allowed the access of thousands of files on public computer kiosks.
Inland Revenue said it was tightening up email security.
- Fairfax Media
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