Detective had three theories about Queensland mum's 1998 disappearance

A former Queensland police detective who led the initial investigation into the 1998 disappearance of Mossman mother Joanne Butterfield has told a coronial inquest he believed it was most likely she had taken her own life.

Ms Butterfield was last seen leaving a home at Mowbray, south of Port Douglas, and hitchhiking late on June 26, 1998.

About two days later, some of her personal belongings were found about 160 kilometres away.

A coronial inquest is investigating whether Ms Butterfield has died and the adequacy of the police investigation into her disappearance.

Graeme Eaton was the lone detective in Mossman when he took carriage of the investigation in July 1998.

His final report in July 2002 concluded three possibilities — that Ms Butterfield had taken her own life, had travelled south and was still alive, or met with foul play while travelling south.

Inquest to hear from male associates

Mr Eaton made a nationwide appeal for information on TV program Australia's Most Wanted in November 1998 but by mid-1999 had formed the view Ms Butterfield "wanted to disappear".

Counsel assisting the coroner Peter Ah Gee asked Mr Eaton about the extent to which he investigated Concetto "Con" Tati, who had been described as an "intimate partner" of Ms Butterfield.

The inquest heard a statement was taken from Mr Tati, then 38, and that Mr Eaton had written a note saying, "Con has a reputation of belting women".

However, Mr Eaton did not recall whether he looked up Mr Tati's Queensland criminal history or what other follow-up enquiries were made.

Mr Eaton said Mr Tati was "certainly a person that needs to be spoken to" but said he did not stand out as a person of "great" interest.

Mr Tati and another associate, Michael O'Donoghue, are due to be examined as witnesses at the inquest this week.

Both men have lawyers representing them during the proceedings. Neither is accused of any wrongdoing.

Mr Eaton told the inquest he was not aware of Mr O'Donoghue during the investigation.

"Specifically with relation to the foul-play hypothesis, did you identify any persons who required elimination as suspects during the course of your investigation?" Mr Ah Gee asked.

"I don't recall identifying anyone, no," Mr Eaton replied.

Mr Eaton was asked about a Cairns phone number that was the most frequent to appear on a call charge record from the landline at Ms Butterfield's home, and whether he ever enquired as to whom it belonged.

Mr Eaton said he did not recall looking into it and that if any avenue of inquiry was not undertaken, it was because the investigation was not "swaying that way".

"I can't respond or provide an explanation to it, Your Honour, primarily because I don't recall every enquiry or every avenue of enquiry I made in an investigation 28 years ago," he said.

Items not sent for DNA analysis

Some of Ms Butterfield's personal belongings, including clothing, a resume and identification documents, were found near a lookout along a cane railway at Pin Gin Hill on June 28, 1998.

An extensive ground search of surrounding cane paddocks and rainforest took place the following month.

Mr Eaton said he would have been "surprised" to find any biological material given the time that had passed.

Mr Eaton agreed with Mr O'Donoghue's barrister James Sheridan's proposition that the absence of blood or fluids on Ms Butterfield's items would have contributed to a decision not to send them for DNA testing.

However, he said: "There was a heavy focus on the suicide [theory]."

"In my view, discarding those items at such a prominent location would not be the behaviour of someone who has been involved in foul play of a missing person,"

he said.

A day after reporting her mother missing, Ms Butterfield's daughter, Skye Lemon, received some of her mother's other personal effects in an envelope addressed to her at school.

The envelope, postmarked July 29, 1998, bore Ms Butterfield's handwriting.

Mr Ah Gee asked Mr Eaton whether he had considered if someone else could have mailed it.

"I don't recall having that thought process but it wouldn't make sense to me that someone would have posted it on her behalf," he said.

The envelope was checked for fingerprints but none were found.