Concerns have been raised about a senior police officer's conflict of interest in the murder investigation of Shandee Blackburn, 23, who was stabbed more than 20 times while walking home from work in 2013 in Mackay in north Queensland.

Key points: A pre-inquest hearing is told a senior Mackay police officer is the aunty of one of the suspects in the murder case

A pre-inquest hearing is told a senior Mackay police officer is the aunty of one of the suspects in the murder case When suspect William Daniel found out police were searching for him in NSW, he did not phone them back, but instead called his aunty, Mackay Detective Sergeant Samantha Bliss

When suspect William Daniel found out police were searching for him in NSW, he did not phone them back, but instead called his aunty, Mackay Detective Sergeant Samantha Bliss However, Coroner David O'Connell says concerns about the adequacy of the police investigation are beyond the scope of the inquest

Ms Blackburn's former boyfriend, John Peros, was charged in September 2014 with her murder, but was acquitted in 2017.

A pre-inquest hearing has been told senior Mackay police officer, Detective Sergeant Samantha Bliss, is the aunty of one of the other suspects in the case, William Daniel.

Craig Eberhardt, who represented Mr Peros at the trial and will represent him at the inquest, told today's hearing that when Mr Daniel found out police were searching for him in New South Wales, he had not phoned them back, but instead called his aunty.

He said Detective Sergeant Bliss travelled to Broome in Western Australia to speak to the former partner of Mr Daniel and then took a statement.

"Why was the prime suspect's aunty involved in the investigation?" Mr Eberhardt said.

"Did that have any impact on the decision to charge Mr Peros instead of Mr Daniel, and does it have anything to do with the inactivity on the case in the last two years?"

Mr Eberhardt told the court there was a substantial case against Mr Daniel.

"The police had at least two suspects," Mr Eberhardt said.

"One … had a criminal history of carrying and using knifes, and was seen by a lifelong friend 500 metres from the scene of the attack, just minutes after it happened.

"He [Mr Daniel] told lies and by his own admission, took flight because of the suggestions he was responsible.

"Mr Peros was not confronted by any of those problems, yet he was arrested and charged."

Conflict of interest not disclosed

Mr Eberhardt told the court the conflict of interest for Detective Sergeant Bliss and arresting officer Lisa Elkins was not disclosed prior to the decision to arrest and charge Mr Peros.

Coroner David O'Connell said concerns about the adequacy of the police investigation were beyond the scope of the inquest.

"The issues around Bliss don't have any great assistance for me on the issues for this inquest," Mr O'Connell said.

"They might be relevant for a criminal matter, but not an inquest."

The inquest is set down for July and is expected to take two weeks.