In late 2015, Gaynor successfully argued before the Federal Court that his termination infringed the freedom of political communication implied in the constitution. Last month, though, justices Nye Perram, Debbie Mortimer and Jacqueline Gleeson accepted an appeal by the Australian Defence Force and upheld the validity of Gaynor's termination.

Given similarities between this context and the treatment of public servants who express their views on political matters, the judgment and its ramifications deserve scrutiny.

The full court's decision predominantly rested on two related grounds. First, the bench found that primary judge Robert Buchanan had erred in conceptualising the constitutional protection as a "right" afforded to Gaynor. They said: "The proposition that the implied freedom does not involve, nor does it recognise or confer, any personal rights on individuals in the same way the first amendment to the US constitution does, is an observation which has been made repeatedly in almost every case dealing [with] the freedom of political communication." While Buchanan had initially acknowledged this in the judgment, his subsequent application of the law suffered from a "rights-based analysis" defect.

Second, the full court disagreed with the subject of Buchanan's analysis. The first instance decision had assessed the constitutional validity of the decision to terminate Gaynor's commission, a discretionary power granted under federal regulations. According to Perram, Mortimer and Gleeson, the correct approach was instead to consider whether the authorising regulation itself was invalid for disproportionately burdening the implied freedom. While they accepted that the regulation "was capable of making an officer pay a price for [their] communications", it was nevertheless "suitable, necessary, and adequate in balance with respect to any burden it imposes" on the freedom of political communication. Gaynor's termination was therefore valid.

The former army officer, a one-time Senate candidate for the Australian Liberty Alliance, has vowed to appeal to the High Court. If Australia's top judiciary agrees to hear the case, it will provide a much-needed opportunity to clarify this complex area of law.

Gaynor perhaps represents an unfortunate test case for the ventilation of important free speech issues. Many would no doubt strongly disagree with the views he stridently espoused. His "antipathy to overt tolerance or support of homosexuality" and "statements critical of adherents of Islam", as Buchanan described, could be labelled homophobic and Islamophobic. Some might even go so far as to say the implied constitutional protection for political communication simply does not, or should not, extend to such comments. Yet the High Court did state in 2013: "History ... teaches that abuse and invective are an inevitable part of political discourse."

Gaynor's views were expressed in his own time, in his capacity as a private citizen and not while he was on duty or in uniform. While his comments did draw a connection with the ADF, he was not purporting to speak on its behalf. There is something deeply unsettling about the government seeking to regulate an individual's views, whether public servant, army reservist or ordinary citizen.

It is on this point that the final substantive paragraph of Buchanan's initial judgment resonates: "the applicant's commission was terminated because of the publication of his private views about political matters. The fact that those publications were at variance with [ADF] or government policy, or were in terms of which some may strongly disapprove, or were critical of [ADF] policies or instructions, does not appear to me to be sufficiently connected with any legitimate legislative aim to displace the freedom of political communication implied in the constitution."

These comments are equally apposite in the Australian Public Service context in light of numerous examples of the federal bureaucracy taking disciplinary action against public servants for expressing views critical of government policy. As I have argued before, government employees cannot be silent members of society or gagged from expressing political opinion.

In recent years, the ADF has engaged in a process of cultural change. It was in this context that the full Federal Court came to its decision: "it is not difficult to conclude that it was open to the [ADF] to reach the conclusion that the retention of [Gaynor] in the army was not in the interests of the army, given the weight placed on the fundamental changes in attitude and policy about diversity in the [ADF], measured against the content, manner and tone of [Gaynor's] public statements."

To some, this reasoning is compelling and the end result just. Indeed, the court's disapproval of Gaynor's comments was thinly veiled. But if he had instead criticised the government's defence policy, would the outcome have been different? How do we rationally distinguish between political statements that deserve constitutional protection and those that do not?

The High Court has a preference for sidestepping such big-picture questions and focusing solely on the narrow point of law in dispute. For the sake of public servants wanting to express their political views without fear of reprisal, we can only hope the High Court is more ambitious when it delivers the final word in the Gaynor saga.

John Wilson is the managing legal director at Bradley Allen Love Lawyers and an accredited specialist in industrial relations and employment law. He thanks Kieran Pender for his help with this article. john.wilson@ballawyers.com.au