Joanne had been trying to leave Charlton in 2007, when she was strangled in her Hughesdale home.

Charlton told police he found her after taking his dog for a walk.

Appealing the conviction Charlton’s defence claimed the jury got it wrong because they weren’t given proper directions during the trial.

His lawyer telling the Court of Appeal there wasn’t enough weight given to the defence claims that someone else could have attacked Joanne.

“This was plainly a murder – the question was who was criminally liable,” Paul Smallwood said.

Charlton has always maintained he didn’t kill Joanne.

During his murder trial his defence claimed Joanne could have been killed by her estranged brother, by another man known to her, or during a random break in.

“He gets to come out of prison, lucky him he gets a day trip,” Joanne’s sister Lisa Hennessy told 9News following the hearing.

“I hope he gets another 10 years put on his sentence for putting our family through all this again.”

Charlton is currently serving 24 years behind bars.

Three court of appeal justices will now rule on his conviction.

It is expected the decision will be handed down in the next few weeks.