The report called for a range of reforms to the way judges instructed juries in sexual abuse trials, including the removal of two long-standing instructions only remaining in Queensland and one other state.

One such piece of advice, the Longman direction, is to be given when a significant length of time has elapsed between the alleged incident and its reporting

A judge is supposed to warn it would be "be dangerous to convict" a defendant on the basis of the alleged victim's testimony alone, because a delay in reporting means the evidence could not be properly assessed.

The royal commission's Criminal Justice report handed down earlier this year noted while Victoria had enacted legislation to abolish the need for the ruling and New South Wales made similar changes but Queensland and Western Australia were yet to reform the area.

New South Wales crown prosecutor Nanette Williams told a commission hearing the shift in her state had "significantly changed" the landscape of prosecuting historical child abuse matters.

"The Longman direction, when it was given, in my own opinion, was the kiss of death to many prosecutions," she said.

"It was very difficult for a Crown case, no matter how credible, how reliable, how strongly the complainant gave evidence - it was very difficult for the prosecution to withstand that direction.

"It was a direction - and I've talked about this with my colleagues over the years, that you would see the juries attending to the directions given by the presiding judge and it was almost visceral, a juror's direction to hearing that direction, ???dangerous to convict'.

"They are heavy words."

That phrase remains in the Supreme and District Court Benchbook and judges rely on while presiding over trials.

Former Queensland Law Society president Bill Potts said the Longman direction should remain because historical sexual abuse allegations were often vague and not able to be "nailed down to a particular date or time or place".

"That, therefore, makes it very difficult for a person who is defending the allegation to establish an alibi or to call relevant witnesses," he said.

"This is particularly the situation when, for example, the allegations were made 30 or 40 years ago.

"So it's about ensuring a fair trial both for the complainant and the defendant."

In the Criminal Justice report, the commission declared "the time" had arrived to change the laws relating to that direction and several others, including one remaining in Queensland and New South Wales.

In its final recommendations, handed down on Friday, it recommended all states and territories should consider codifying judicial directions, following Victoria's lead and review their legislation to comply with a host of recommendations.

Those included ensuring there was no requirement to warn juries "that delay affects the complainant's credibility", and to avoid language such as "dangerous or unsafe to convict".

Abolishing the requirement to give the Markuleski direction, telling jurors a reasonable doubt concerning the truth or reliability of the complainant's evidence on one count "must" be taken into account in assessing their evidence generally, should also be scrapped.

The Bar Association of Queensland could not be reached for comment on Friday afternoon but cautioned against limiting the directions open to the trial judge in its submissions.

Another recommendation called for states to remove "good character" as a mitigating factor for offenders when the good character helped them offend in the first place.

The government was yet to act on a Queensland Sentencing Advisory Council recommendation for such a change.

Queensland Premier Annastacia Palaszczuk did not commit implementing all of the commission's 409 recommendations but promised to "consult broadly with survivors, interest and advocacy groups and the broader community to ensure that we get these reforms right".

"This report is an important opportunity to acknowledge the devastating and harrowing experiences of survivors of childhood sexual abuse and the efforts of all that provide support to them," the Premier said.