Child Youth and Family has had to do a U-turn in court, after repeatedly and incorrectly reporting that a man was a sex offender.
The agency had been repeating the information since 2001 and did not correct its reports to the Family Court until last year, despite being told three times it was wrong.
CYF has apologised to the man.
The man has complained to the Privacy Commissioner that family members - including his son - and other members of his community believed he was a sex offender.
He had been assaulted and his house attacked as a result, he said.
The Privacy Commissioner has backed his complaint, finding the Ministry of Social Development (MSD) - which is responsible for CYF - interfered with the man's privacy and failed to take reasonable steps to check the accuracy of the information.
The commissioner has referred the case to the Director of Human Rights Proceedings.
CYF social workers told the Family Court in 2001 that the man had sex convictions.
However, he had never been charged, prosecuted or jailed for such offending.
MSD told the Privacy Commissioner's investigation the man had previously received a 12-month suspended sentence for assaulting children in his care after he found them engaging in sexualised behaviour.
The ministry believed those events had been misinterpreted by CYF staff.
CYF's deputy chief executive, Murray Edridge, said it acknowledged the harm done to the man, and the agency was in talks with his lawyer to reach a settlement.
In a separate case, the government called today for a review of a CYF case where the agency told a court a father had a history of violence, when he did not.