THE Special Commission of Inquiry into the alleged cover-up of child sexual abuse by Catholic priests in the Hunter won't hand down its findings until next year.

The inquiry opened in February and was due to report to the government by September 30.

But Premier Barry O'Farrell told question time yesterday that Commissioner Margaret Cunneen had sought an extension and would report on February 28 next year.

"We should all agree that it is obviously more important that the relevant matters are properly and thoroughly investigated," he said.

"No one wants any shortcuts when it comes into matters as serious as these."

Mr O'Farrell said the inquiry had more than a hundred private hearings with more than a hundred summons to produce its documents.

Ms Cunneen is investigating the circumstances in which Detective Chief Inspector Peter Fox, whose allegations of a Church cover-up sparked the inquiry, was asked to stop probing certain matters.

She has heard evidence from senior police including two assistant commissioners and two superintendents, as well as three senior Catholic officials, including Australian Catholic Bishops Conference secretary Father Brian Lucas.

The inquiry concentrated on two priests, serial sex offender Father Denis McAlinden and convicted paedophile Father James Fletcher, both dead.

Commissioner Cunneen is also examining the extent to which Catholic church officials co-operated with police. 

AAP