The former ice addict boyfriend of a woman allegedly murdered on Phillip Island has denied killing her.

Disabled pensioner Sam Karamanis told the Supreme Court he did call Robyn Hall a "slut" after she admitted having sex with Paul Dalton but did not murder her.

Mr Dalton has pleaded not guilty to murdering Ms Hall on December 19, 2012, at his brother Matthew's Cape Woolamai holiday house on Phillip Island.

The Crown claims Mr Dalton attacked and killed Ms Hall at the Lantana Road house before transporting her body to an unknown location and disposing of it.

Ms Hall's body has never been found.

Mr Karamanis said he and Ms Hall had been regular users of the drug ice before they argued and broke up in early December 2012.

He claimed Ms Hall later admitted during a phone call that she had slept with Mr Dalton.

"I pretty much called her a slut and hung up the phone after that," Mr Karamanis said.

"It was a bit of a heated argument on the phone but I wasn't going to put up with it, I pretty much hung up."

Mr Karamanis said he later threatened to call Mr Dalton's partner to tell her Dalton had had sex with Ms Hall.

He agreed he had possibly sent one text message to Mr Dalton at 9.11pm on December 18 2012 which said: "I be telling your missus you been f...ing Robyn too you mutt."

"We would have exchanged quite a few phone calls between each other, as the fact was we were both quite ropeable with each other at the time. We both made verbal threats and other threats towards each other over that situation," Mr Karamanis said.

Asked by defence barrister Daniel Gurvich if he had threatened to kill and bury Ms Hall so that no one would ever find her, Mr Karamanis replied, "No."

He denied killing Ms Hall, arranging for her to disappear or telling anyone to go to Phillip Island to do such a thing.

Crown prosecutor Mark Rochford, QC, told the jury Mr Dalton attacked Ms Hall on the verandah of the holiday house and the injuries she suffered caused significant blood loss.

"While she was bleeding and either dead or dying, she was dragged through the garage with her heels along the ground," Mr Rochford said.

"She was placed on the floor before being dragged into the rear storage area and laid on the gravel floor and covered by cardboard boxes."

Police began investigating Ms Hall's disappearance after her family and friends raised concerns about her welfare.

The Cape Woolamai house was examined on the night of January 24 last year, where police used luminol spray to detect traces of blood on the verandah.

After his arrest, Mr Dalton told police he had argued with Ms Hall about telling their respective partners about their affair but he denied killing her.

The trial, before Justice Lex Lasry, continues.

guess or speculate as to what had happened.

Mr Dalton had pointed to others who could have been involved, including Ms Hall's former boyfriend Sam Karamanis, a disabled pensioner and ice addict.

Mr Karamanis, who was called as a witness during Mr Dalton's trial, admitted calling Ms Hall a "slut" after she told him she had had sex
with Mr Dalton, but denied murdering her.

Justice Lasry said Ms Hall's last series of text messages were to Mr Karamanis at 5.09pm on December 19, 2012.

The judge said Mr Karamanis had been involved in drugs and might have had the opportunity to be involved in Ms Hall's death.

Mr Dalton wiped away tears as he was told he was free to leave the court.

Justice Lasry's decision to throw out the case against Mr Dalton came after defence barrister Daniel Gurvich argued on Thursday, in the jury's absence at the end of the prosecution case, that Mr Dalton had no case to answer.

"There is an assertion that there was an assault on the verandah where the deceased sustained injuries causing significant blood loss and the evidence does not support that in my submission," Mr Gurvich said.

"That Ms Hall was dragged through the garage dead or dying is not supported by the evidence or, in any event, that my client had any involvement in that activity if it did happen.

"It's asserted that clothing was used by the accused to clean up the crime scene and there is in my submission no evidence at all of
that."

Mr Gurvich said there was no proof of murderous intent.

Crown prosecutor Mark Rochford, QC, had told the jury Mr Dalton attacked Ms Hall on the verandah and the injuries she suffered caused significant blood loss. Police began investigating Ms Hall's disappearance after her family and friends raised concerns about her welfare.