A Queensland man has been sentenced to life behind bars for the shooting murder of his girlfriend.

A Brisbane Supreme Court jury took two hours on Friday to find Christopher Charles Koani, 34, guilty of murder for the second time, after the High Court had quashed his original conviction.

His girlfriend Natalie Leaney, 26, was found with a gunshot wound to the head in the driveway of their home south of Brisbane in March 2013 and died a short time later in hospital.

The court heard victim impact statements from Natalie Leaney's family. 'The world as we knew it has gone and it will never be the same,' her mother Deborah Leaney said.

Christopher Charles Koani, 34, was found guilty of murder for the second time, after the High Court quashed his original conviction

Koani told police she'd been shot by burglars but was charged with murder two days later.

He was found guilty of murder in November 2015 but appealed against the conviction in the Queensland Court of Appeal, which was unsuccessful.

He took the case to the High Court, which unanimously ruled last August that the appeal should be allowed and ordered his conviction be quashed and the matter re-tried.

Koani admitted the manslaughter of Ms Leaney on the opening day of the new trial on Monday, but the Crown did not accept his plea and continued with the murder charge.

He had also tried to plead guilty to the lesser charge during his initial trial.

This week, Koani's barrister, Bruce Mumford, urged the jury to keep an open mind and pointed to evidence that the gun had a faulty mechanism, the Courier Mail reported.

Natalie Leaney was shot dead in the driveway of her home south of Brisbane in 2013

'The issue in the trial is whether the shot that killed Natalie Leaney was fired deliberately,' Mr Mumford said.

'The prosecution have to prove the existence of that intent.'

The court also heard victim impact statements from Ms Leaney's family.

'The world as we knew it has gone and it will never be the same,' her mother Deborah Leaney said.

'It has been four years, 10 months and 23 days since you destroyed our family and stole our daughter Natalie's life.

'And here we are, still sitting, waiting for justice to be heard.

'It takes it back to that time again and the horrific pain and heartache we suffer and continue to suffer.

Ms Leaney's family gasped and burst into tears when the unanimous decision was read out, the ABC reported.

Koani did not show any emotion as he stood standing in the dock.

Outside court, Ms Leaney's family told reporters that they were glad justice had been served, but have been warned Koani could appeal again.