A fourth suspension over Mason case in Qld

A fourth child safety worker has been stood down over the case of dead Queensland toddler Mason Lee.

Child Safety Minister Shannon Fentiman last week announced three staff members at the Caboolture Child Safety Service Centre had been stood down on full pay pending an ethical standards investigation over the 21-month-old's death in June.

Mason was found covered from head to toe in injuries three months after his release from hospital and Ms Fentiman has admitted a 300-page internal report into the department's handling of the case exposed "serious errors of judgment" on behalf of staff.

Another nine staff members face disciplinary proceedings.

"Following advice from the department's ethical standards unit, a fourth person has been stood down in relation to my department's interactions with Mason Lee and his family," the department's Director-General Michael Hogan said in a statement on Monday.

"This individual is one of the 12 staff members who were last week referred to the ethical standards branch."

The ethical standards investigation could take up to 12 weeks.

Ms Fentiman has committed to releasing a final report into the case which is expected by January, but has faced calls for her to release the initial report.

The initial report is being considered by an independent review panel, the Queensland coroner, the Family and Child Commission and police.

In announcing the actions against the 12 staff, Ms Fentiman said she had "never seen anything like it" because only two other staff had been referred to ethical standards during her time as minister.

Three people, including Mason's mother and stepfather, have been charged with manslaughter.

Opposition Leader Tim Nicholls said the further disciplinary action was more proof child safety services in Queensland were in crisis and the only people in denial were Ms Fentiman and Premier Annastacia Palaszczuk.

"The time is long past due for Shannon Fentiman to be replaced," he said.