The Mabo case is widely recognised as a turning point in Australian legal history, as it challenged the colonialist assumptions upon which our nation was founded and acknowledged the realities of Indigenous dispossession.

When, in 1992, the High Court of Australia recognised that the Indigenous population held a connection to the land predating European settlement, a door opened for Indigenous Australians to reclaim at least some of their rights to parts of our nation.

However, 20 years on, Aboriginal land rights remain as contested and as tenuous as ever. Of particular note is the Commonwealth Government's plan to establish a nuclear waste dump in the Northern Territory at Muckaty, north of Tennant Creek.

Since the 1990s, the Commonwealth has led a long and troubled search for a remote place to store the country's radioactive waste. The Howard Government tried to locate a site in South Australia but a spirited campaign by Aboriginal custodians, the wider community, and the state Labor Government ended that push.

Despite promising no mainland dump site ahead of the 2004 federal election, the re-elected Howard government announced three possible Northern Territory sites in July 2005. As part of that effort, the Coalition government then turned to the Aboriginal Land Councils to encourage them to identify other possible waste sites on Aboriginal Land. In 2007, the Commonwealth Government accepted a nomination by the Northern Land Council for a site to be assessed, 120km north of Tennant Creek on the Muckaty Land Trust.

That nomination has been the subject of continuing controversy. Many of the traditional owners of Muckaty argue that they were never consulted, and others say that they were not consulted in a meaningful way and never consented to the nomination. Most importantly, many traditional owners allege that they were never informed about the details of the proposal to dump nuclear waste on their land, the danger that this might present to them and their families, the potential impact of the proposal on their sacred sites, and the fact that the nature of the legislation and the material involved meant that they were effectively giving up their land in perpetuity (i.e. forever).

It is these concerns that lie behind the current Federal Court action where traditional owners opposed to the dump plan are challenging the actions of both the Northern Land Council and the Commonwealth.

Under the heavy-handed National Radioactive Waste Management Act passed earlier this year, once Muckaty is declared a nuclear waste dump, the site is effectively resumed by the Commonwealth for as long as they wish. Presumably this will be as long as the life of the nuclear waste, which will be centuries. The land will be taken from traditional owners and might only be returned to them at the whim of the federal government and the Land Council.

Much has been made of the potential environmental implications of building a nuclear waste facility at Muckaty, not least because its most vocal public opponents are conservation groups, medical experts, and Greens. Lesser understood though is that the Muckaty case heralds a significant unwinding of Aboriginal land rights.

If successful, the Commonwealth will appropriate Aboriginal land owned under indefeasible Torrens title. Native title is ephemeral and easily extinguished when, for example, the government deems Aboriginal land necessary for public infrastructure works. In contrast, land ownership based on an indefeasible title is legally regarded as much more substantial, just as you or I might own our homes and the land on which they are built.

Hence the Commonwealth's preparedness to accept and act upon a deeply flawed and contested nomination at Muckaty, a home to at least seven Aboriginal family groups, represents a retrograde move in the history of Indigenous land rights.

The Northern Land Council maintains that it nominated Muckaty as the site of a Commonwealth nuclear waste facility after receiving the informed consent of one of the local Aboriginal family groups, who they claim are the only legal owners of the land in question. But other local Aboriginal family groups and moieties, who are acknowledged by law as beneficiaries of the Muckaty Land Trust, insist that they were never properly consulted about the nomination or the proposal to construct a nuclear dump on their land, and that they never agreed to it.  

At present, the Northern Land Council and the Commonwealth's legal position is that even if the waste dump site at Muckaty has been nominated by the Northern Land Council without recourse to proper processes of consultation and obtaining informed consent, then the facility could still go ahead. From an ethical and legal viewpoint, this position is untenable, and in the 21st century such reasoning should not be accepted.

More importantly, the notion that the Commonwealth can take possession of Aboriginal land against the wishes of its Aboriginal owners and without proper consultation counters an important principle raised in the Mabo No 2 case nearly two decades ago; namely, that the Australian government has a fiduciary duty to hold certain land on trust on behalf of its Aboriginal people.

A fiduciary duty is the obligation that a more powerful party has to another, more vulnerable, party in its relationship with it. The purpose of a fiduciary duty is to avert abuses of power by those in authority or positions of power.

In the context of native title, the Mabo No 2 case considered the proposition that Australian governments are bound by a fiduciary duty to protect the interests of Indigenous groups. The Muckaty case has the potential to finally determine the extent of the fiduciary duty that our Commonwealth Government owes to Aboriginal people to honour Indigenous land rights, an issue raised in Mabo No 2 but never resolved.

As the pressure for, and resistance to, a radioactive waste dump at Muckaty both grow, it is clearly time to address the conflict between the Commonwealth's duty to protect Indigenous Land Rights and their desire to dump waste on this contested site in the NT.

George Newhouse is a member of the legal team acting for a group of Muckaty traditional owners challenging the nomination of their land as the site of a national nuclear waste dump.