Four years later, Ms Hinder believes she knows the real reason for her suspension: disability discrimination. The Blue Mountains woman has taken the religious charity to court, alleging her former bosses targeted her as a gambling addict.

But is gambling addiction a disability as Ms Hinder claims? A NSW magistrate has cleared the way for the law to decide.

Ms Hinder worked for eight years at the Upper Blue Mountain Corps Family Store before she was suspended for two weeks with pay in 2011, the NSW Civil and Administrative Tribunal heard. She decided to quit rather than accept the suspension.

But Ms Hinder said documents obtained last year showed her new bosses had privately – and falsely – accused her of stealing money from the till. Three weeks before the suspension, she had shared with her supervisors a document called "Kath's Story" that outlined her past struggles with gambling addiction.

The Salvation Army testified that no theft allegations were made in 2011 and previous ones were found to be unsubstantiated. It said the suspension decision was made by an HR officer unaware of the problem gambling problem.

Ms Hinder's complaint to the Anti-Discrimination Board NSW this year was dismissed as lacking substance. But NCAT disagreed on appeal, giving her a green light to proceed with the complaint.

"Ms Hinder may be able to establish that her particular issue with gambling is a disability because it is 'a disorder, illness or disease that affects a person's thought processes, perception of reality, emotions or judgment or that results in disturbed behaviour'," Magistrate Nancy Hennessy found.

"I understand her to be submitting that a tendency to steal money is a characteristic that is generally imputed to people who have a gambling problem."

Karen O'Connell,​ a law researcher at UTS, said disability had a suitably broad legal definition in NSW legislation.

"We don't want people to be stopped at the first gate and not take their complaint any further forward because of one definitional issue," Dr O'Connell said. "The other hurdles [in proving discrimination] are more than enough to protect against someone receiving protection who shouldn't."

Paul Delfabbro​, a psychology professor at Adelaide University, was more wary of such a broad definition.

"It would be very hard to argue that problem gambling is a disability," he said. "Many problem gamblers can be very cognitively able and usually have no physical disabilities. They just have very strong urges to gamble which leads to them spending too much money."

At the level of brain structures, "there are currently no neurobiological markers available to diagnose whether someone has pathological gambling," Monash University researcher Adrian Carter said. The brains of gambling addicts may or may not show changes in function, which means diagnoses must be based on behaviour.

The latest edition of the "psychiatrist's bible", the Diagnostic and Statistical Manual V, treats severe problem gambling as an addiction like alcoholism or drug dependency, rather than an impulse-control disorder.

Discrimination law in NSW excludes illegal drug addiction from disability status. But the Australian Chamber of Commerce and Industry wants workplace laws to also exclude gambling addiction – as US law does – to give employers greater certainty.

"Expanding disability out of the health space into the addiction space is a huge jump," chief executive Kate Carnell said.

While society needed to do more to help people with addictions, long-term or transitory, "it's not a workplace issue", Ms Carnell said.

Ms Hinder, the Salvation Army and the Anti-Discrimination Board declined to comment.

What is a disability?

There are five definitions of disability under the Anti-Discrimination Act 1977 (NSW). These refer to bodily and mental dysfunction, malformation and disfigurement, disease-causing organisms, learning impairments and distorted thinking that leads to disturbed behaviour.

In a discrimination claim, the disability can be past, present or future. It can be actual or merely perceived by the discriminator.

In the Hinder v Salvation Army case, neither party cited a legal judgment on whether gambling addiction counts as a disability.

What is gambling addiction?

Gambling addiction is a subset of problem gambling. Also known as "pathological gambling", the behaviour was classed as an addiction in the latest edition of the Diagnostic and Statistical Manual used by psychiatrists. This was after research suggested the brains of gambling and drug addicts shared neural similarities.

However, gambling addiction is diagnosed using nine non-medical criteria, including lying to conceal gambling, using others' money, betting more money over time and losing relationships.