Adelaide Airport has pulled a series of conservation group advertisements from its concourse billboards in the days leading into the ALP national conference, while initially retaining industry and gas-sector messaging.

The Murray-Darling Conservation Alliance (MDCA) had a 'Save the Murray' advertisement removed from an electronic billboard in an Adelaide Airport concourse after the airport deemed it 'too political.' MDCA co-director Craig Wilkins confirmed the ad had been contracted to run from 13 July to 26 July but had disappeared by the morning of 22 July. The advertising agency JCDecaux told MDCA that Adelaide Airport considered its ads to cross a line on political content The Guardian.

The Bob Brown Foundation had a similar experience. Its ads, running in four locations at Adelaide Airport from 20 July to 26 July, were due to be pulled from noon on 23 July. JCDecaux told the foundation that the removal came at Adelaide Airport's request and that, as landowner, the airport has the final decision on what runs on its premises The Guardian.

A third group, the Adelaide Park Lands Association, had its 'Stop the Chop' billboard for the main airport exit declined by Adelaide Airport. The ad was due to be displayed on a Tuesday and was declined the preceding Friday. Adelaide Park Lands Association president Mat Monti is named on the campaign The Guardian.

A spokesperson for Adelaide Airport said the airport has guidelines for advertising on its land that is political in nature, and that advertisements not meeting those guidelines will be removed.

The timing is awkward, to put it mildly. Labor politicians, including Prime Minister Anthony Albanese, were arriving through Adelaide Airport for the ALP national conference that weekend. Conservation ads vanishing from the concourse while party faithful walk past is not a good look for anyone involved, least of all the airport operator.

The selective application of the 'too political' test is where this gets harder to swallow. After the conservation ads were pulled, ads from Santos, the Minerals Council of Australia, and Independent Schools Australia were still running on the Adelaide Airport concourse. An 'Australia runs on natural gas' ad was also on rotation. That ad includes a political authorisation message from Samantha McCulloch, chief executive of Australian Energy Producers. Under Australian electoral law, authorisation messages are required for electoral or political advertising. So the gas industry's messaging carries a statutory political tag, but it apparently passed the airport's guidelines while 'Save the Murray' did not.

The Guardian understands the 'Australia runs on natural gas' ad at Adelaide Airport has since also been stopped, but only after the initial inconsistency was reported.

Bob Brown described Adelaide Airport's pulling of the environmental ads as 'Trump-lite behaviour' and called on Prime Minister Anthony Albanese to insist the ads be reinstated immediately.

In my view, the core issue here is not whether a private landowner can set advertising guidelines. Clearly, it can. The problem is the inconsistency of application. When an environmental campaign with a conservation message is yanked for being 'too political' but a gas industry ad carrying a formal political authorisation stays up, the guideline looks less like a neutral standard and more like a content preference. The airport's belated removal of the gas ad does not fix the initial disparity; it simply confirms that the original decision-making was hard to defend on a principled basis.

For anyone who has watched the regulation of political advertising in Australia, the episode is a familiar illustration of the gaps in the system. There is no overarching, consistently applied test for what constitutes 'political' advertising in privately owned but publicly accessible spaces. Airports, shopping centres, and transit infrastructure operators each set their own rules, and those rules are applied at the discretion of the operator, often with minimal transparency. The result is exactly what has played out at Adelaide Airport: a conservation group loses its contracted run while an industry group's politically authorised messaging stays live until the inconsistency becomes politically untenable.

The ALP conference context sharpens the stakes. When the governing party's senior figures are walking through a concourse stripped of environmental messaging but lined with resources industry ads, the optics write themselves, whether the airport intended them or not. Whether Prime Minister Albanese responds to Bob Brown's call for intervention is another matter. Federal governments have historically been reluctant to wade into the advertising decisions of private airport operators, and there is little indication that pattern will shift here.

What this episode does, though, is put the spotlight firmly on JCDecaux and Adelaide Airport's content moderation process. The guidelines exist, but their application is opaque. Conservation groups contracted for a fixed run have had their ads pulled mid-campaign, at a time of peak political traffic, with no clear explanation beyond a vague reference to 'political' content. The gas industry ad, also carrying a political authorisation, was allowed to run until the discrepancy surfaced. If the guideline is genuinely neutral, it needs to be applied neutrally. If it is not, the airport should say so plainly. Right now, it is doing neither.