QUEENSLAND Opposition Leader Lawrence Springborg will give evidence for several hours at the inquiry into the suicides of three teenagers following the closure of an Ipswich mental health facility.

Mr Springborg was the state's health minister when the Newman government closed the Barrett Adolescent Psychiatric Centre at Wacol in January 2014.

Within eight months of the closure, former inpatients Will Fowell, Talieha Nebauer and Caitlin Wilkinson-Whiticker took their own lives.

Mr Springborg will spend the morning of February 26 in the commission of inquiry witness box.

The Southern Downs MP, who is scheduled to attend from 9.30am-1pm, is one of 45 witnesses listed to give evidence over four weeks.

Mr Springborg supported the centre's closure, arguing at the time that services closer to the patients' homes would meet their needs.

Other witnesses include centre founder and psychiatrist Dr Cary Breakey; director of Mental Health, Queensland, Dr Aaron Groves; and headspace state manager Amelia Callaghan.

Patients and family members of the deceased will give evidence on March 4, 7 and 8.

Media will not be allowed to publish any information that identifies these witnesses.

The draft witness list was released during the inquiry directions hearing in Brisbane on Thursday.

The hearing was the precursor to the inquiry itself.

Former judge Commissioner Margaret Wilson will oversee the investigation into whether or not the teenagers' deaths were linked to the closure of the state's only long-term residential mental health facility for adolescents at risk of suicide.

The investigation starts on February 15 and is expected to run for four weeks.

A lawyer for Mr Springborg asked the inquiry for extra time to look at the scope of questioning the MP would face because he was concerned about "prejudicing" witnesses' interests.

"It is ... not satisfactory for those appearing for persons whose interests may be severely prejudiced by the outcome of this to be told for the first time on February 15 (hearing start date) what are the key issues ... to focus on," the lawyer said.

The request was supported by the legal representatives of other witnesses.

Ms Wilson changed the three-day notice period to four days.

Ms Wilson will hand her report and recommendations to Premier Annastacia Palaszczuk on June 24.

The inquiry is also expected to aid in the coronial inquiry into the teenagers' deaths.

*If you need mental health support please phone Lifeline on 13 11 14 or the Suicide Call Back Service 1300 659 467.

EARLIER: THE Barrett Adolescent Psychiatric Centre commission of inquiry directions hearing is underway in Brisbane.

The hearing is the pre-cursor to next month's investigation into the deaths of three teenagers following the closure of the Wacol mental health facility two years ago.

Will Fowell, Talieha Nebauer and Caitlin Wilkinson-Whiticker took their own lives not long after the then Newman government closed the Barrett Adolescent Psychiatric Centre in January of 2014.

The commission of inquiry will investigate if the teenagers' deaths were linked to the closure.

About 45 witnesses, including patients and medical staff, will give evidence during the inquiry which begins officially on February 15.

The media was locked out of the inquiry for most of this morning as Commissioner Margaret Wilson heard legal argument about non-publication orders.

The inquiry is expected to re-open to the public and journalists when it re-convenes at 2.30pm today.

*If you need mental health support please call Lifeline on 13 11 14 or the Suicide Call Back Service 1300 659 467.