IN part two of The Chronicle's Unsolved Crime series, we speak to the sister of murder victim Theresa Binge about her 12-year fight to have the mother-of-three's killer brought to justice.

"I BET if my sister was a white girl murdered in Brisbane then her killer would have already been found and brought to justice."

Those are the sentiments of Elizabeth "Lily" Bartholomew, who for the past 12 years has been fighting to see her sister's killer brought to justice.

But she is not holding her breath.

Aboriginal mother-of-three Theresa Beatrice Binge, 43, was last seen alive drinking with a man around midday at the Royal Hotel in Goondiwindi on July 18, 2003.

CLICK HERE FOR A TIMELINE OF THE MURDER INVESTIGATION

Ms Binge had been out the previous night and had been seen at the Victoria Hotel in Goondiwindi where she attended a disco with friends.

She was last seen wearing silver/grey tracksuit pants, a yellow and black striped rugby jersey and sandshoes.

The Boggabilla mum's relatives reported her missing on July 21 after she failed to attend a family gathering.

I do not believe a thorough police investigation was carried out

Ms Binge's badly beaten body was found on July 29 in NSW under a road culvert on Boomi Rd, about 10km west of Goondiwindi.

She was found naked with her pants around her ankles, with bruising to her jaw, forehead and with several scratches on her thighs.

Police revealed at the time drag marks had been found in the dirt near where the body was dumped, which suggested she had been killed at another location.

I hope the people I think are responsible will continue to look over their shoulders for the rest of their lives.

Forensic testing conducted at the time revealed she had not been sexually assaulted, and the exact cause of her death remains a mystery.

The distinctive rugby jumper she was wearing and one of her blue sandshoes has never been recovered.

A joint Queensland and New South Wales Police investigation called Strikeforce Flairs was established to hunt down Ms Binge's killer.

RELATED: Someone must know who murdered my sister

Sixteen detectives from both sides of the border investigated the murder and identified six suspects, but to this day no one has been charged over Ms Binge's murder.

A $250,000 reward remains in place for information leading to the arrest and conviction of the killer.

Ms Bartholomew told The Chronicle she had no doubt whatsoever who was responsible for her sister's vicious and brutal murder.

... I will never stop fighting for her; I could not live with myself if I did. The person responsible is going to get caught, I know it in my heart.

She said it was time for those in the community who know what happened to come forward to give her family closure.

The Chronicle is unable to name the people Ms Bartholomew believes are responsible for her sister's murder for legal reasons.

"I have my suspicions who is responsible but I cannot prove it," she said.

RELATED: Still no closure for family of murdered woman

"One of the scumbags even had the hide to help us look for her after we reported her missing.

"I hope the people I think are responsible will continue to look over their shoulders for the rest of their lives."

Ms Bartholomew said she was disappointed at the way the investigation was handled and believes more could have been done to bring her sister's killer, or killers, to justice.

There are people still alive who know the truth and they need to come forward and have the guts to tell police what they know.

She admitted rumour and innuendo over the years about what happened that fateful night had taken a toll.

"I do not believe a thorough police investigation was carried out," she said.

"There are people still alive who know the truth and they need to come forward and have the guts to tell police what they know.

RELATED: $100k reward to solve decade-old murder case

"They certainly never searched one particular person's house . . . why did that person buy a brand new mattress and sofa only to be seen throwing it out at the tip several days later? Who does that?

"Everyone knows it was him. Even the white folk in town believe he murdered my sister.

"It was a Mickey Mouse investigation where everything was swept under the carpet.

I have no doubt in my mind that if my sister was a white girl then her murder would have been solved by now and justice would have been served.

"I have no doubt in my mind that if my sister was a white girl then her murder would have been solved by now and justice would have been served."

Ms Bartholomew recalled the moment after days of searching paddocks, riverbanks and bushland when investigators ushered her into a room to tell her a woman's body had been discovered.

She said it still haunted her to this day.

"Her murder has affected our family unbelievably," she said.

"It was heartbreaking to learn the truth and to know we would never see her again.

"I just could not understand how someone could do this to her and to another human being.

"But I will never stop fighting for her; I could not live with myself if I did.

"The person responsible is going to get caught, I know it in my heart."

RELATED: Coroner to review Theresa Binge murder case

A NSW coronial inquest into Ms Binge's death was held in Moree in 2008 and Deputy State Coroner Jacqueline Milledge subsequently found "the manner of death is homicide by person or persons unknown".

A number of people were also called to give evidence at a closed Australian Crime Commission hearing in 2011, but none of the information they provided was able to assist police.

The case has since been referred to the NSW Cold Case Squad.

We constantly seek members of the community to come forward and provide police with any information.

A NSW Police spokesman said they were not in a position to discuss any aspects of the investigation.

"The death of Therese Binge is an open unsolved homicide case under the responsibility of the Unsolved Homicide Team," they said.

"A reward is in place for information leading to the arrest and conviction of person/s responsible for Ms Binge's death.

"We constantly seek members of the community to come forward and provide police with any information."

ANYONE WITH ANY INFORMATION SURROUNDING THERESA BINGE'S MURDER IS URGED TO PHONE CRIME STOPPERS ON 1800 333 000.

TIMELINE OF EVENTS:

• July 17, 2003: Theresa Binge is seen drinking at the Victoria Hotel in Goondiwindi.
• July 18: Ms Binge is last seen alive about midday at the Royal Hotel in Goondiwindi.
• July 20: Ms Binge's relatives report her missing to police after she fails to attend a family gathering.
• July 29: Aboriginal searchers find Ms Binge's naked body under a culvert on Boomi Road, 10km west of Goondiwindi.
• July 31: An autopsy is performed in Newcastle but a cause of death could not be established.
• 2004: Police announce Ms Binge's death is being treated as a homicide investigation. Police say they believe Ms Binge was murdered at another location before her body was dumped in the culvert. Ms Binge's daughters visit the site where their mother's body was found and make a passionate plea for information about her death. The NSW State Coroner announces it is reviewing the case.
• 2008: A coronial inquest into Ms Binge's death is held in Moree.
• 2009: Deputy state coroner Jacqueline Milledge ruled the cause of death as "homicide by person or persons unknown" and referred the case to the NSW Police Cold Case Squad.
• 2011: Australian Crime Commission holds a series of closed hearings where several people give evidence but the information they provide is unable to assist investigators.