It wasn't the first time he had uttered those words in a court dock.

It was just over 20 years ago when Sloane, then aged 48, was sentenced to eight years' jail for strangling his former mother-in-law to death after prosecutors accepted a manslaughter plea and dropped murder.

The similarities between the 1995 killing and the murder of Renee Mitchell, of which Sloane was found guilty by a jury on Thursday, are extraordinary.

Both occurred in the Lake Macquarie suburb of Windale, near Newcastle, after Sloane had arrived unannounced at the victim's house following an extended period of animosity between killer and victim.

Both were vulnerable women who were first attacked in their own home.

And both times Sloane had initially denied any knowledge of the deaths, or even being in their homes, before slowly leaking information to authorities as the net tightened and the evidence became irrefutable.

The jury members who convicted Sloane of Ms Mitchell's brutal November 2014 stabbing death were not aware of Sloane's history of killing until after they had found him guilty.

He admitted he had savagely attacked the aged care worker, stabbing her four times in the chest and once in the throat, before dumping her body at Bangalay Reserve.

However, he pleaded not guilty to murder, raising a partial defence of "substantial impairment", which he said affected his capacity to control himself at the time of the killing. The jury rejected these claims.

His former mother-in-law, 72-year-old Barbara Wilson, was living alone in a place she had called home for more than 40 years when police found the widow's body in her bathtub on June 5, 1995.

The bath plug was in place, there was some water still in the tub and Mrs Wilson's body and hair appeared to have been submersed in water.

With the discovery that the plug had a hole, clothing which had been "placed by someone who intended to have a bath" and her purse containing $200 still in her house, investigators had initially suspected the widow had slipped, hit her head and drowned.

But the autopsy quickly proved something more sinister – drowning was excluded and the cause of death was determined as "manual strangulation".

"DNA testing of material under the deceased's fingernails established that the material most likely originated from the deceased herself, which suggests that she must have been grasping at the hand or hands around her throat in a struggle with her killer," Justice David Hunt said on sentencing.

"...I am satisfied on the medical evidence that the attack upon her involved substantial violence."

Mrs Wilson had fought bravely with her killer.

Inside her house, police found two cups which had been used and rinsed, and an uncovered plate of biscuits – it suggested to them she had let someone in and had been cordial.

A man had been seen entering the place on the evening of June 1 – four days before her body was found.

Investigators quickly discovered that Sloane and his mother-in-law had had a testy relationship since the breakdown of the killer's marriage with Mrs Wilson's daughter, Sharyn Stone.

Sloane had blamed his former wife for the loss of his father's life savings, which the couple had borrowed to start up a business in Queensland.

The business floundered after Sharyn Stone found Sloane had been involved in a long-term affair, and after they divorced in early 1994, Sloane began to harrass his elderly mother-in-law in an effort to locate his former wife.

She refused to tell him.

Sloane continued to deny any knowledge of Mrs Wilson's death until he was caught on tape during a conversation with his son three months after the death (a son to another marriage).

Within 12 months, Sloane had admitted to being involved in the death. But he still tried to downplay his role to authorities.

He said he had been just walking past Mrs Wilson's home when he decided to visit "on the spur of the moment" after drinking eight to 10 schooners, two cans of full strength beer and a can of Jim Beam and coke.

(It should be noted that Sloane's apparent dependence on alcohol was a factor in Mrs Mitchell's murder).

He claimed they were still good friends and had put the animosity behind them, spending two-and-a-half hours together before an argument erupted about Sloane's deceased former father-in-law.

And then it occurred – he claims he had put his hand up when Mrs Wilson came towards him and fell, hit a chair before both hit the ground.

Sloane then panicked and put his mother-in-law's body in the bath and left.

But Justice Hunt was having none of it, nor previous accounts made by Sloane to police.

"I am unimpressed by any of those different versions, and I am left with the conclusion based upon the medical evidence that the attack upon the deceased involved substantial violence," he said.

"The Crown accepts that the killing was not premeditated, but it does not accept that the incident itself was merely a spur of the moment one.

"It is manifestly clear to me that the prisoner grabbed the deceased by the throat for an appreciable period.

"No satisfactory explanation has been given to exclude the inevitable conclusion in all the circumstances that the action was done as a hostile act, affected to at least some extent by the animosity which he held towards the deceased."

Justice Hunt sentenced Sloane to eight years' jail, with a non-parole of five years.

But it was not the only piece on Sloane's criminal record which points towards his bizarre and abhorrent character.

He was found guilty of assault occasioning actual bodily harm, breaking and entering into a house at night, and two charges of assault.

They were in Queensland and the complete facts were not available to Justice Hunt, who noted: "...the remarks of the judge in Queensland District Court sufficiently identify the circumstances of the offences to show that the offences arose out of suspected sexual intrigue and somewhat immature conduct on the part of the prisoner".

Newcastle Herald