A correspondent writes:
I’m a volunteer [firefighter]… and part the area we cover includes a Department of Defence establishment which obviously has special conditions around who can enter the grounds and areas under their control. Our brigade has had numerous calls to this establishment … normally as part of as part of an automated building fire alarm activation. While in a lot of specific cases common sense usually prevails, I’m wondering what rights do we have … [under our State fire brigades’ legislation] to enter these premises or grounds when these areas are controlled by Commonwealth legislation?
I’ve taken out the references from the question that would identify the jurisdiction from which this question comes from in order to make the question generic. Given the national focus of this question, the answer will be the same in Queensland as it will be in New South Wales, Victoria, Tasmania and so on around the country.
The critical law here is the Australian Constitution and in particular, s 109 which says:
When a law of a State is inconsistent with a law of the Commonwealth, the latter shall prevail, and the former shall, to the extent of the inconsistency, be invalid.
Or to put it in plain English, a state law is invalid if it is inconsistent with a valid Commonwealth law. (Territory law must also be consistent with Federal Law – see Australian Capital Territory (Self Government) Act 1988 (Cth) s 28 and Northern Territory Self Government Act (Cth) s 51).
The State and territory fire brigades operate under state or territory legislation. Those Acts give the fire services a great deal of authority and power including the power to enter upon private land in order to respond to a fire call, to force open buildings and other things and to take all sort of action to control the fire or other emergency. But if there’s a valid Commonwealth law that is inconsistent with those provisions, the Commonwealth law will prevail.
A Commonwealth law is inconsistent with a State law if it is impossible to comply with both at the same time or if it is clear that the Commonwealth law is intended to ‘cover the field’ that is to be the entire law on a subject area. In that case any State law would be inconstant with that federal intention to ‘cover the field’ and therefore invalid (an issue being played out with the issue of ‘same sex’ marriage with the states and territories, unsuccessfully, looking for a gap in the ‘field’ that is covered by the Commonwealth law on marriage; see The Commonwealth v Australian Capital Territory  HCA 55).
The Commonwealth cannot make a law on anything it wants. The Commonwealth Parliament is a parliament of limited power; it can only make laws with respect to the subject matters listed in the Constitution, in particular in s 51. One of the exclusive powers of the Commonwealth is the power to make laws with respect to defence (Australian Constitution s 51(vi); see also ss 69, 114 and 119).
So the local fire brigade can enter onto Commonwealth land and do all the things they are allowed to do under State law unless there is a valid Commonwealth law that says that they cannot do that; and, with respect to a defence establishments, there is such a law.
The Defence Act 1903 (Cth) Part VIA deals with ‘security of defence premises’. Defence security officials can ask a person seeking to enter defence premises to provide evidence of their name and address and undergo a limited search. If the person refuses they may be denied access to the premises and may be detained. A defence security official can ask the person in control of a vehicle if they consent to the vehicle being searched and if permission is refused the official may refuse to let the vehicle onto the defence premises. A special defence security official can do all those things, demand identification and conduct searches of people seeking to pass a defence access control point or on defence premises, without the person’s consent. There are a myriad of other provisions relating to secure the defence base that we need not consider in detail (For other provisions restricting access to defence areas, see the Defence Act 1903 (Cth) ss 71-72S; see also Defence (Prohibited Wharves And Buildings) Regulations 1950 (Cth) and Defence Force Regulations 1952 (Cth) rr 35 and 53)). For our discussion the really important provision is the Defence Act 1903 (Cth) s 72P, that says:
A person commits an offence if:
(a) the person enters or is on:
(i) defence premises; or
(ii) defence accommodation; and
(b) the person is not authorised to be on the premises or accommodation.
Given that s 72P is a valid law of the Commonwealth, any power in the state fire service to enter the premises and take action there to investigate if there is, or respond to, a fire would be inconsistent with that provision and therefore invalid. The question becomes ‘what does it mean to be ‘authorised’?’ Any number of people could be authorised to be on defence premises for any number of reasons and they don’t all have to be members of the ADF. So if the defence force allows the fire brigades to enter the land, either on a single occasion or, hopefully, because there is an actual understanding between the brigades and the ADF, then they are authorised to be there so no offence is committed.
In terms of all the regulatory rules of the brigades, the provisions that identify the chain of command, determine the functions of the brigades etc; all of that still applies as it’s not inconsistent with a Commonwealth law. Provisions that allow the brigades or the incident controller to order a place to be evacuated or to compel people to leave the area would, I suspect (and without going through the Acts chapter and verse) be inconsistent with the Defence Act where that allows other people to determine who is to be on defence premises; so you couldn’t require ADF personnel to evacuate the area. Having said that I’m sure you could ask and I would expect that they would comply except where there are legitimate security reasons not to, but they would not commit an offence if they did not.
The answer to the question ‘what rights do we have … [under our State fire brigades’ legislation] to enter these premises?’ is you have no right at all, as a ‘right’ would be inconsistent with the Defence Act 1903 (Cth), but if you are authorised, that is allowed – even invited – to come on to defence premises, then you can and you can do, cooperatively with the ADF, what you need to do to deal with the emergency.