Richard Boyle could have walked away with a pile of cash from his former employer.

Instead he turned down a settlement offer from his former boss, the Australian Taxation Office (ATO), to tell the media about what he saw as some unfair debt collection tactics adopted by the agency.

Now he faces the possibility of 161 years in prison.

The Adelaide-based public servant worked at the ATO for years as a debt collector, but turned whistleblower last year to reveal disturbing practices at the agency to a recent joint Fairfax-ABC Four Corners investigation.

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Mr Boyle, 43, is charged with 66 offences including using a listening device to monitor a private conversation, recording another person's tax file number and disclosing protected information.

The information and summons sheet lists tax commissioner Chris Jordan as the informant, with his signature on it.

Now the question is whether Mr Boyle may be protected by public interest disclosure laws passed in 2013, specifically relevant to public servant whistleblowers.

In February 2018, the ATO tried to settle with Mr Boyle over an alleged breach of the Public Service Code of Conduct, offering him a payout and a statement of service, with no admission of liability.

The catch would also be that he would be unable to speak to media about what he knew.

But Mr Boyle decided the public had a right to know what was going on at the ATO. He would not stay quiet. He rejected the ATO's offer.

During the ABC-Fairfax investigation Mr Boyle claimed that, in 2017, some Adelaide office staff were instructed to seize funds from the bank accounts of taxpayers assessed to owe the ATO money, regardless of their personal circumstances.

The agency has the legal authority to issue what is known as a garnishee notice in order to directly deduct debts from bank accounts or earnings.

Changes for small businesses facing tax disputes

Mr Boyle's revelations were crucial to the media investigation, along with several others who spoke out, and to a number of important changes that followed.

The tax ombudsman, the inspector-general of taxation, a position formerly held by Ali Noroozi, announced a review into garnishee notices.

The ATO also announced a pilot trial, allowing small business taxpayers in dispute with the agency access to "independent reviews" — something that for years had only been available to the big end of town.

Labor announced it would appoint a new second commissioner to hear small business tax disputes, as well as tax clinics to help vulnerable taxpayers get free legal advice. The Federal Government has also since announced tax clinics.

Small business taxpayers wanting an external review of an adverse tax decision through the Administrative Appeals Tribunal (AAT) will now also be able to contact the office of the Australian Small Business and Family Enterprise Ombudsman (ASBFEO), with heavily discounted rates (initial consultations are $100) for advice.

For the general taxpaying community, and particularly vulnerable Australians who cannot afford costly legal advice on complex tax matters, this is a huge win.

For Mr Boyle, the consequences have been devastating.

When the ATO became aware of the media investigation last year, Mr Boyle had his rental unit in Edwardstown raided by officers from the ATO, and he lost his job.

At the time of the raids, the ATO said protecting taxpayer confidentiality was "critical for the integrity of Australia's tax and super systems".

"The commissioner is committed to doing everything possible to secure taxpayer information, and will pursue cases where taxpayer confidentiality has been compromised," the agency said at the time.

The agency has refrained from commenting on the case publicly since.

Is there a public interest disclosure defence?

Professor A J Brown, from Griffith University and Transparency International, is an expert on whistleblower laws.

He told ABC News he thinks Mr Boyle could rely on the Public Interest Disclosure Act 2013 whistleblower legislation for federal public servants.

"As the first major case of its kind since the 2013 laws, where a federal whistleblower has been charged with public disclosures, this could be a very significant test case," he said.

At the same time the Federal Government has announced tougher protections for private sector whistleblowers, but there are worries that these still do not go far enough.

The Labor Party has pledged, that if it wins government, it will revisit all whistleblower laws so that private and public disclosures all fall under one piece of legislation.

In February, Opposition Leader Bill Shorten said it would create an Australian whistleblowing act, consolidating all mainstream whistleblowing legislation into one location.

"Whistleblowers should be treated the same, regardless of the type of workplace they're in," Mr Shorten said. "But right now, our whistleblower laws are opaque and inconsistent."

Labor has also made an election promise to financially reward those who expose crime and corruption.

Under its plan, whistleblowers would receive a percentage of the penalties that eventuate from the wrongdoing, as is the case in the United States.

But outgoing Industrial Relations Minister Kelly O'Dwyer labelled the plan "wacky" and said the Government would not offer whistleblowers financial rewards.

In the meantime, Mr Boyle fights on. He will return to court on March 29.