This is one of a special series of posts exploring the public law implications of the COVID-19 pandemic. For more information on the Gilbert + Tobin Centre’s work in the area of public law and public health, see here.


This is the first of two posts AUSPUBLAW is featuring considering executive power and COVID-19. Shreeya Smith’s accompanying post is here.

“The Executive Government is the arm of government capable of and empowered to respond to a crisis be it war, natural disaster or a financial crisis” (Pape v Federal Commissioner of Taxation (2009) 238 CLR 1 at [233].)

We are in such a crisis. And we are seeing executive governments – in particular, the federal executive government – responding to that crisis. As the federal, state and territory Parliaments adjourn their sitting dates, the question arises: do the executive governments have power to take the actions they are taking in response to COVID-19? This post specifically looks at the power conferred on the federal executive by the Biosecurity Act 2015 (Cth). To be valid, the Biosecurity Act must be supported by a constitutional head of legislative power. The most likely source of power, the quarantine power under s 51(ix) of the Constitution, has never been directly examined by the High Court of Australia. This post argues that there is a real question as to whether the biosecurity measures under the Biosecurity Act can be supported by the quarantine power. Instead, to validly act during this crisis, the federal executive may need to rely on other sources of power.

Executive powers

The executive branch needs power to act in an emergency. Yet there is no mention of “emergencies” in the Constitution nor any constitutional category of “emergency” powers. Executive responses to emergencies are therefore governed by the ordinary framework of law.

During the COVID-19 crisis, the federal executive could potentially exercise the following powers (see Williams v The Commonwealth (2012) 248 CLR 156 at [22]):

  1. powers conferred by statute;
  2. the prerogative power of the Crown; and
  3. the “nationhood” power.

Starting with the first category: statutes. The federal Parliament only has legislative power in relation to the subject-matters specified in the Constitution. Therefore, any statute conferring federal executive power must fall under one or more of those heads of power.

During the COVID-19 crisis, the most relevant head of power is the “quarantine” power under s 51(ix). In 1908, the Commonwealth Parliament exercised its quarantine power to pass the Quarantine Act 1908 (Cth) – the predecessor to the Biosecurity Act. The Quarantine Act was never the subject of a constitutional challenge. Indeed, the scope of the quarantine power has never been directly examined by the High Court. That power is discussed further below. The external affairs power under s 51(xxix) is also relevant. For example, the National Health Security Act 2007 (Cth) was enacted to give effect to the World Health Organization’s International Health Regulations by establishing a framework for coordination and sharing of information during public health emergencies. That coordination framework is being used during COVID-19. Finally, the Commonwealth also has power under s 96 to grant financial assistance to any state “on such terms and conditions as the Parliament thinks fit”.

The second category, prerogative power, is sourced in the authority historically exercised by the Crown as recognised by the common law. That power cannot be expanded (British Broadcasting Corporation v Johns [1965] Ch 32 at 79). Therefore, reliance on it during the COVID-19 crisis depends on finding an existing category of prerogative power. One possibility is the “power of self-protection” (see Twomey at 325-326), which includes the power to respond to “a national emergency, [where there is] an urgent necessity for taking extreme steps for the protection of the Realm” (Burmah Oil Co Ltd v Lord Advocate [1965] AC 75 at 136). However, there are two potential hurdles to relying on a prerogative power of self-protection in the current crisis. First, the self-protection power is typically associated with war or domestic incursions. As the prerogative power cannot be expanded, it is unclear whether protection from a pandemic would fall into that existing category. Second, there is doubt as to whether a prerogative power of self-protection even subsists as part of Australian law (see Moore, at Ch 1, fn 354).

The third category, the so-called “nationhood” power, is separate again. To the extent that it exists (cf Twomey at 327ff.), it is implied from ss 51(xxxix) and 61 of the Constitution and the existence and character of the Commonwealth as a national government (Victoria v The Commonwealth (“AAP Case”) (1975) 134 CLR 338 at 397). It is a power “to engage in enterprises and activities peculiarly adapted to the government of a nation and which cannot otherwise be carried on for the benefit of the nation” (Commonwealth v Tasmania (“Tasmanian Dam Case”) (1983) 158 CLR 1 at 252-253). The idea is that the federal executive must have power to act on matters that are truly “national” in nature: either in those areas that fall outside the scope of state legislative and executive powers, or at least in those areas where there is no real competition with the states (Tasmanian Dam Case at 252-253). However, the nationhood power cannot be invoked to set aside the distribution of powers between the Commonwealth and states and between the three branches of government (Pape at [127]). It also cannot be used merely because programmes can be conveniently formulated and administered by the federal government (AAP Case at 398).

The COVID-19 pandemic is a truly national emergency. It is a public health emergency that is not limited to state boundaries. However, it is not the case that states have no power, or insufficient power, to deal with the crisis within their borders. Under the Constitution, while federal legislative power is limited to the enumerated heads of power, the residual power is left to the states. That includes matters of public health and emergencies, which have historically been managed at the state level. There are also practical reasons for this. As put by the Acting Premier of Queensland during the 1918-1919 influenza outbreak: “being on the spot, we know the local conditions and the circumstances and we are in a better position to gauge what should be done than those living in Melbourne could possibly be”.

As a result, state Parliaments have power to legislate on matters of public health and emergencies. And, as they exercise plenary legislative power, they can generally define “emergency” and confer executive powers without significant boundaries. State executives, therefore, lawfully, wield broad powers to act in times of a public health emergency. There are two relevant limits. First, state legislative powers are subject to the operation of s 109 of the Constitution (which provides that Commonwealth law prevails in the event of an inconsistency with state law). Second, conferral of emergency powers on the executive must be temporary or risk breaching the requirement that Parliaments not permanently abdicate their legislative powers (see Lee et al at 7, 175-176).

Biosecurity Act 2015 (Cth)

This accepted division of power between the Commonwealth and the states, and between legislatures and executives, has been pushed to its limits by the Biosecurity Act. Under that Act, the federal executive manages activities used to prevent the introduction and spread of listed diseases into Australia. Before adding a disease to the list, the federal Director of Human Biosecurity (the Chief Medical Officer) must consult with, relevantly, the chief health officer for each state and territory (s 42(2)). COVID-19 was added as a “listed human disease” on 21 January 2020.

The COVID-19 crisis is governed primarily by Chapter 8 of the Act. Chapter 8 concerns “[b]iosecurity emergencies and human biosecurity emergencies”. The Governor-General declared COVID-19 to be a human biosecurity emergency on 18 March 2020.

The Act, and Chapter 8 in particular, represents an unprecedented expansion of power by the federal executive.

First, the subject-matter of the Act invades into terrain traditionally managed by the states. For example, under the Act, federal government officers and employees, and members of the Australian Defence Force, can issue “human biosecurity control orders” which impose “biosecurity measures” on individuals (Biosecurity Act, ss 60, 82, 563). Those measures include: requirements to provide contact details; restricting the individual to their place of residence; wearing protective clothing or equipment; being decontaminated; undergoing examinations and providing body samples; or receiving vaccinations or medication (Biosecurity Act, Ch 2, Pt 3, Div 3). These are activities relating to individuals within state boundaries on matters of public health.

Second, the Biosecurity Act extends the federal executive’s power over the federal and state legislatures through two “Henry VIII clauses” in Chapter 8. A “Henry VIII clause” is one in which Parliament delegates power to the executive to make laws that override other statutes. It is a rarely conferred power in the federal executive to promulgate laws.

The Henry VIII clauses at ss 477(5) and 478(4) state respectively that a requirement determined under s 477(1), or a direction given under s 478(1), applies despite any provision of any other Australian law, including state laws. The concurrent operation of state and territory laws with the Act, provided for in s 8, is subject to these Henry VIII clauses (s 8(2)(c)).

Under s 477(1), the federal Health Minister

may determine any requirement that he or she is satisfied is necessary: (a) to prevent or control … (ii) the emergence, establishment or spread of the declaration listed human disease in Australian territory or a part of Australian territory.

The Minister has used this power to, among other things, impose overseas travel bans; to impose emergency requirements for remote communities; to prohibit cruise ships from entering Australian ports; to prohibit trading by retail outlets in international airports; and to prohibit price gouging in relation to essential goods. Under s 478(1), the Health Minister may also “give any direction, to any person” if satisfied that the direction is necessary for the same reasons. These determinations are not conditional upon consultation with the Health Ministers of the states and territories.

How has the Biosecurity Act justified this expansion of power? Let us return to the three categories of federal executive power discussed above.

First, these powers of the federal executive are obviously conferred under a statute; here, the Biosecurity Act. Section 24 of the Act sets out a range of possible heads of legislative power under which the Act could have been made, as well as a severability clause in case of a successful constitutional challenge. The constitutional heads of power listed in s 24 are the quarantine power; external affairs power; trade and commerce power; fisheries power; aliens power; corporations power; territories and Commonwealth places power; postal power; sickness benefits power; and census and statistics power.

Recall the biosecurity measures listed above – providing contact details; restricting the individual to their place of residence; wearing protective clothing or equipment; being decontaminated; undergoing examinations and providing body samples; and receiving vaccinations or medication. These measures apply to the states, so they cannot be wholly supported by the territories and Commonwealth places power. The measures are not included in the WHO’s International Health Regulations and so, in the absence of a new international agreement, would unlikely be supported by the external affairs power. As the measures apply to individuals, they would unlikely be supported by the trade and commerce, fisheries, corporations or postal powers. As the measures apply to Australian citizens, they would unlikely be supported by the aliens power. And due to their subject-matter, it seems unlikely that the sickness benefits power or census and statistics power would apply.

That leaves us with the quarantine power under s 51(ix) of the Constitution. We can surmise the High Court’s general approach to determining whether these biosecurity measures are laws “with respect to” quarantine. If the laws were to be challenged, the Court would be required to judge whether they operate in such a way that they can be said to be connected to the quarantine head of power. The practical, as well as the legal, operation of the laws must be examined. The connection to quarantine cannot be “so insubstantial, tenuous or distant” that it cannot sensibly be described as a law “with respect to” the quarantine power (see Re Dingjan; Ex parte Wagner (1995) 183 CLR 323 at 368-369). The quarantine power does extend to matters ancillary or incidental to quarantine (see Wragg v New South Wales (1953) 88 CLR 353 at 386).

Reynolds has proposed the following core elements of the quarantine power: for a “public health need, detention or isolation for a specific period on the basis that a person has or might have a particular disease” (at 172).  Restricting an individual to their place of residence squarely fits within this definition. Providing contact details so that officers can find at-risk individuals to quarantine may be considered incidental to detention and isolation. However, there is a real question whether the other measures could be characterised as incidental to detention and isolation. Instead, requiring an individual to wear protective items, be decontaminated, undergo examinations and receive vaccinations or medication, appears to be more to do with sanitation and public health generally – matters regulated by the states (see Reynolds at 176). Indeed, in a rare discussion of the quarantine power, Latham CJ held in obiter that the power would not support a Commonwealth law requiring citizens of the states to submit to vaccination or immunisation (Attorney-General (Vict) v The Commonwealth (“Pharmaceutical Benefits Case”) (1945) 71 CLR 237 at 257):

Under s 51 (ix) the Commonwealth Parliament has power to make laws with respect to quarantine. Quarantine legislation may be regarded in most, if not all, of its aspects as a particular form of public health legislation. In relation to quarantine the Commonwealth Parliament has full powers of legislation. It can not only provide that money shall be spent upon quarantine, but it can devise and put into operation a whole compulsory system of quarantine under which duties can be imposed upon persons and penalties inflicted for breach of the law. But in relation to other aspects of public health the Commonwealth (once again leaving out of account the Territories) has no such power of legislation. The Commonwealth can, in my view, authorize the expenditure of public money on inquiries, investigations, research and advocacy in relation to matters affecting public health. But the Parliament could not pass a law requiring citizens of the States to keep their premises clean or to submit to vaccination or immunization.

Therefore, it is not self-evident that all biosecurity measures under the Biosecurity Act will be supported by the heads of power listed in s 24.

If they are not, the executive will need to rely on another source of power. A second option may be the Crown’s prerogative power. However, that option will depend on pandemics falling within an existing category of prerogative power, such as the power of self-protection, and that category of prerogative power applying in Australia.

A third option may be the nationhood power. Under s 475(1)(a) in Chapter 8 of the Biosecurity Act, the Governor-General may declare that a human biosecurity emergency exists if the Health Minister is satisfied that, relevantly, a listed human disease is posing a severe and immediate threat, or is causing harm, to human health “on a nationally significant scale”. It may be accepted that the COVID-19 pandemic is a crisis on a national scale. However, it is not clear that the federal executive’s leadership role in this crisis is a necessary one as opposed to merely convenient.

In 1919, at the height of the influenza outbreak, the Acting Premier of Queensland refused to allow returned soldiers onshore in an attempt to “protect Queensland from the possible infection that may result from any carelessness at this stage”. The result was a stand-off between the state and the Commonwealth. The headline in The Brisbane Courier read: “Soldiers Due Today. A Constitutional Crisis: Which authority will prevail?”

Today, the answer is undoubtedly the Commonwealth. However, until the High Court defines the scope of the quarantine power under s 51(ix) of the Constitution, we will not know whether its grab for power has been successful.

Stephanie Brenker is a Barrister at the Victorian Bar. She is one of the co-authors of COVID-19 and the Law of Australia: an online textbook, organised by subject area, providing guidance on the laws made by the legislature, executive and judiciary (and administrative tribunals) of the Commonwealth and each State and Territory in response to the COVID-19 pandemic.

Suggested citation: Stephanie Brenker, ‘An Executive Grab for Power During COVID-19?’ on AUSPUBLAW (13 May 2020) <>