The boss of Queensland's crime and corruption watchdog has accepted full responsibility for the accidental release and prolonged availability of secret Fitzgerald inquiry documents.
Despite the admission, Crime and Misconduct Commission (CMC) chair Ross Martin says it was a senior staffer who caused the blunder in the first place.
Mr Martin told the Parliamentary Crime and Misconduct Commission (PCMC) on Friday that he'd become aware in May last year that confidential documents had been made publicly available in the Queensland State Archives.
The problem, attributed to a classification error, was not fixed until September.
Mr Martin said he accepted an explanation in May last year from the CMC's director of information management, Peter Duell, that it was just a clerical error and it had been fixed.
Mr Martin said he did not realise until September it hadn't been resolved and was only made aware earlier this month just how sensitive the released documents were.
The documents from the landmark Fitzgerald inquiry into police corruption contained information, including unproven allegations, about targets and informants.
They weren't supposed to be released until about 2055.
Mr Martin, under persistent questioning from the PCMC, admitted Mr Duell had caused the error.
"I've seen enough of the facts to be satisfied that there is a strong prima facie case of maladministration," he said of Mr Duell's conduct.
Although he later conceded he was "ultimately responsible".
"All leaders recognise when something like this occurs, leadership responsibility is significant," he said.
"All leaders also understand the vulnerability of their position when a staff member makes a mistake and something like this happens."
Mr Martin said he had no reason to doubt Mr Duell and asked Official Solicitor to the CMC Sidonie Wood to investigate what he saw at the time was a "relatively modest mistake".
But Mr Wood never reported back to him and he had never chased the matter up, he admitted.
Mr Martin said he didn't alert the PCMC, which oversees the CMC, of the blunder earlier because he didn't see it as a "real" problem - only a hypothetical one.
"The prospect of some crook 20 years ago suddenly waking up and deciding in this narrow window `I'll go and have a look' was minuscule," he said.
The PCMC is also investigating the accidental shredding of about 4000 Fitzgerald inquiry documents.
Mr Martin last week announced his resignation as chair of the CMC, but said he was leaving for health reasons.
His resignation came amid pressure from Premier Campbell Newman and other ministers for him to accept responsibility for the blunder.