The man whose DNA was found on a cigarette butt outside alleged murder victim Corryn Rayney's Como home may have a murder conviction, according to police notes.
The Lloyd Rayney murder trial was told yesterday the man was also living with an "extremely well known" sex offender in the same suburb as the Rayney house.
Det-Sgt Mark McKenzie told the Supreme Court he had written notes during the murder investigation relating to a man named Ivin Eades who was living with Allan Lacco - an "extremely well known" sex offender - in Como.
Mr Rayney is fighting an allegation he wilfully murdered his estranged wife after she returned home from a dance class on the night of August 7, 2007.
The court has already been told a cigarette butt seized by police from the verge outside the Como home contained DNA from Mr Eades.
Yesterday, the court was told the butt appeared to be recently deposited on the verge when it was seized weeks after Mrs Rayney's disappearance on August 22, 2007.
The court has been told a police officer who claimed to have seen Mrs Rayney in Victoria Park the night she died had done a traffic check on a driver with the surname Eades. Yesterday, Det-Sgt Mark McKenzie was asked by defence lawyer David Edwardson about an entry in his notebook during investigations that noted Eades' name and an abbreviation for "previous murder conviction".
The officer had also noted a Como address where the man was living and agreed police knew Mr Eades had been living with Lacco.
Justice Brian Martin then asked whether he would be presented with more information about whether the "alternative candidates" being put forward by the defence were realistic candidates.
"The way you have opened it up . . . it is a plain suggestion from the defence that not only is the (murder) investigation inappropriately focused on the accused but that they had some primary candidates right there on the doorstep," Justice Martin said.
Prosecutor John Agius said that if the defence was proceeding that way, extra weeks could be needed to organise material and witnesses.
Det-Sgt McKenzie's evidence revealed that by late August 2007, police considered Mr Rayney a person of interest and believed his behaviour with the media was "suspicious". Mr Edwardson suggested the same could have been said in the Lindy Chamberlain case, before withdrawing the comment.
Det-Sgt McKenzie agreed police had bugged Mr Rayney's home and car by September 6, 2007, with taped calls played in which he discussed the case with Mr Rayney while calling himself the "family liaison officer".