Professor Campbell McLachlan QC – Written Evidence (TWP0003)


Parliamentary scrutiny of treaties: Inquiry into working



I write in reply to your request of 12 May 2020 that I submit evidence in the inquiry launched by the new House of Lords EU International Agreements Sub-Committee (IAC) into how Parliament scrutinises treaties.



1       I am Professor of International Law at Victoria University of Wellington. I have been a visiting fellow inter alia at All Souls College Oxford and am elected to the Arthur Goodhart Visiting Professorship at Cambridge University for 2021–2.

2       An important field of my research has been the study of how national constitutions address the exercise of the foreign affairs power: Foreign Relations Law (Cambridge UP, 2014,FRL’). Chapter 5 examines the role of Parliament in the treaty power and the supervision of the executive, comparing practice in the United Kingdom, Australia, Canada and New Zealand. Treaty scrutiny by Parliamentary committees has been a feature of the constitutional arrangements in Australia and New Zealand (but not in Canada) since the mid-1990s, and so provides a particularly relevant precedent for the IAC to consider.

3       I have continued to publish on the foreign affairs power in the UK, as it has developed in particular in light of Brexit ((2018) 134 LQR 380) and have examined comparative foreign relations law, serving as an international advisor to the American Law Institute Restatement (Fourth) Foreign Relations Law (2012–2018).

4       In 2014, I concluded that, while the Constitutional Reform and Governance Act 2020 (the 2010 Act) ‘is singularly important in itself for what it says about Parliament’s ultimate power over treaty ratification. But reform in the field of parliamentary procedure may offer more tangible benefits. Comparison with the position in Australia suggests in particular that the establishment of a joint select committee with a specific centralised remit for treaty review may provide the most effective focus for parliamentary engagement in the treaty ratification process: FRL [5.89]. The establishment of the present Committee is a very positive step in this direction.

5       I make my comments and recommendations under five heads:

(a)            Scrutiny functions

(b)            Representative democracy

(c) The national interest

(d)            Pre-signature scrutiny

(e)            Select committee powers.


A              Scrutiny functions

6        In the Westminster constitution, Parliament has two functions that may engage its role in foreign affairs: (a) supervision of the executive; and (b) its role as legislator. It is important to keep the two roles distinct in the design of effective scrutiny.

7        One ground for a greater role for Parliament in the treaty-making process is the enlarged impact of treaties on domestic law, affecting Parliament’s position as sovereign legislator domestically.

8        Yet Parliament’s power to supervise the conduct of the executive and hold it to account in its exercise of its foreign affairs power exists independently of Parliament’s legislative function, but is no less fundamental to our constitution than Parliamentary sovereignty’ since: ‘By these means, the policies of the executive are subjected to consideration by the representatives of the electorate, the executive is required to report, explain and defend its actions, and citizens are protected from the arbitrary exercise of executive power:’ Miller (No 2) [2019] UKSC 41, [2020] AC 373, 406, [46].

9        At the same time, it is the executive and not Parliament that is empowered to negotiate and conclude treaties. The United Kingdom is fortunate to have access to sophisticated expertise within the Foreign & Commonwealth Office, as well as an established constitutional mechanism for consultation and advice to Cabinet through the office of Attorney General. These represent significant advantages to the UK both domestically and internationally.

10   Parliament cannot legislate on the international plane. This requires reaching agreement with other states, which must be negotiated by the duly authorised representatives of the government. Parliament cannot convert itself into a negotiating body.

11   The position is different under constitutional arrangements where affirmative consent of the legislature is required. Under Article II(2) of the United States Constitution, where the ‘advice and consent’ of the Senate is required for treaty ratification. In the European Union, where Art 218(6) of the Treaty on the Functioning of the European Union (‘TFEU’) requires the Council to obtain the consent of the European Parliament to conclude certain types of treaties.

12   It is the requirement of consent that has driven the power of the EU Parliament to impose negotiating guidelines on the Council and Commission, whether at the outset or during such negotiations under Rules 114(3) & (4) of the EU Parliament Rules.

13   A formal requirement of consent can have disadvantages. It can lead to rigidity in treaty negotiations. It can also give rise to elaborate avoidance practices by the executive, especially in instances where a majority in the legislature develops hostility to international engagement, as has frequently been the position in the United States. (A recent example is the negotiation of the Paris Agreement as an ‘executive agreement’ without Senate approval, an approach that ultimately weakened the binding obligations in the treaty to control climate change).

14   Under the British constitution, Parliament would have to legislate if it wished to enlarge its role such that its affirmative consent would be required for treaty making, as contrasted with the current negative resolution procedure under s20 of the 2010 Act. The reforms to Parliamentary procedure for the review of treaties in Australia and New Zealand (discussed below) do not as yet go so far as to require Parliamentary consent.

15   This Note proceeds on the basis that the enlarged treaty review role for the UK Parliament is to be undertaken for the purpose of holding the executive to account. Such a role will not seek to insert Parliament into the international negotiation or require that Parliament give its consent to the executive to negotiate or conclude treaties.


B              Representative democracy

16   An important rationale for the Parliamentary scrutiny of treaties is to enhance representative democracy by ensuring that Parliament checks legal obligations assumed on the international plane that may nevertheless affect the lives of British citizens.

17   It is no answer to say that Ministers are directly accountable to the people for their international commitments. In a representative democracy, the mandate of the government only applies to the extent that it can command the confidence of the House of Commons.  The people express their democratic rights through the election of members of Parliament.

18   The development of an effective select committee review can provide a valuable channel for the public to express their views on a proposed treaty action to Parliament. This has been a very important aspect of the process in the Parliamentary committees in Australia and New Zealand. For example, the review by the NZ Foreign Affairs, Defence and Trade Committee (‘FADT Committee’) of the proposed Trans-Pacific Partnership Agreement elicited over 6000 submissions and heard from 255 oral witnesses orally.

19   In order to secure fully the objective of representative democracy in the UK context, it would be necessary to constitute a Joint Committee of both Houses, balancing the expertise available in the House of Lords with the representative character of the Commons. This is the model successfully adopted in Australia (which has a bicameral federal legislature). There is relevant precedent for this approach in the UK, where (outside the EU context) the Joint Committee on Human Rights (‘JCHR’) has been the most active committee to date in reviewing treaties: FRL [5.77]. A joint committee would also present advantages for its powers, outlined below in section E.


C              National interest

20   The purpose of an effective treaty review process is to determine whether ratification of the treaty is in the national interest. The first step in making that determination is to ensure that the government prepare a National Interest Analysis (‘NIA’) with any treaty submitted for Parliament’s consideration.

21   In New Zealand (unlike in Australia) the necessary contents of the NIA are specified in a standing order (SO 397, copy annexed), which requires an assessment of the costs as well as the benefits of ratification. This is much more rigorous than the current form of Explanatory Memorandum used in the UK. The Committee should consider adoption of a codified requirement for a national interest analysis along the lines of NZ SO 397.

22   However, the committee review process in both Australia and New Zealand still suffers from inadequacies that have led to the charge that the committees operate as a rubber stamp of government treaty decisions and not as an effective exercise of Parliamentary scrutiny.

23   Five key enhancements to the existing procedures would be beneficial and should be considered in the UK:

(a)            Providing the Committee with sufficient dedicated staff or advisers with the expertise to provide it with independent research (the most important practical measure);

(b)            Preparation or review of the NIA by a government office independent of the Ministry responsible for negotiating and proposing the treaty measure: Kawharu (2017) Melb JIL 286, 299. This would ensure that appropriate advice could be taken from other government agencies and a dispassionate assessment made of the costs as well as the benefits;

(c) Incorporating an express provision that the Committee is chaired by a member of Parliament who is not drawn from the principal party in government (as is the current position in the IAC);

(d)          Requiring the government to refer a proposed treaty to the Committee on a timetable that allows sufficient time to enable it to hear and consider the evidence and to report to Parliament. The 21 days provided under the 2010 Act is not sufficient for this purpose; and

(e)          Ensuring that the government provide sufficient time in Parliament for debate of the Committee’s report on any significant treaty, should the Committee so recommend.


D              Pre-signature scrutiny

24   The Australia/NZ treaty review procedures operate between signature and ratification. (There is provision in Australia for Parliament or a Minister to refer a draft treaty for pre-signature review, but in practice this has been rarely used).

25   Review post-signature preserves a clear distinction between the role of the executive to determine foreign policy and to negotiate treaties on the one hand, and the role of Parliament to scrutinise the government’s exercise of those powers once they have been exercised but before the state enters into an international commitment and before domestic legislation is required.

26   However post-signature review suffers from the defect that it presents Parliament with an all-or-nothing choice. It can either accept the treaty in the form in which it has been negotiated, or reject it in its entirety. This greatly limits the substantive contribution that Parliament can make.

27   This approach may be understandable in cases where either the treaty is either (a) a multilateral treaty of universal application concluded with many states where it is unrealistic to expect the Parliament of any individual state to be able to shape the direction of the negotiation; or (b) a bilateral treaty of standard form.

28   The position is different in the negotiation of the complex plurilateral or bilateral agreements (see the criteria in Parliamentary Practice in New Zealand, Ch 42). These are a particular feature in the field of international trade, which is a special focus of the IAC’s remit. But similar concerns may well arise in other fields.

29   Here, the limitations of the current Australia/NZ approach have become apparent. Agreements such as the TPP (now CPTPP) have been negotiated without disclosure to or discussion with parliaments of the participating states prior to signature. Yet they are highly complex and will have broad and long-term effects on society. Post-signature review does not provide an effective opportunity to consider those impacts or to make constructive proposals for amendment, as the experience with the CPTPP in New Zealand demonstrated.

30   By contrast, scrutiny of the government’s objectives at the outset and at periodic intervals throughout the negotiation would allow Parliament to check those objectives and to address with the government areas that may require adjustment in light of existing domestic law or Parliament’s overall view of domestic priorities.

31   For this reason, I welcome the UK Government’s proposal to lay before Parliament an Outline Approach and Round Reports on free trade agreement: DIT White Paper (February 2019), 9. This approach should be broadened to provide the basis for detailed scrutiny by the IAC and should apply to treaties outside the free trade context where the like considerations apply.


E              Select Committee powers

32   Finally, Parliament must ensure that the Committee has sufficient powers to enable it to conduct its business, in particular by ensuring the production of documents and the attendance of witnesses. The adoption of such powers by standing orders will greatly enhance voluntary compliance with the Committee’s requests.

33   There are three powers that should be strengthened in Parliament’s standing orders in light of the recent experience of Parliamentary inquiries into foreign affairs (discussed in FRL 5.99–5.112; House of Commons Library ‘Select committees: evidence and witnesses’ (2 June 2016, ‘HCL Report’); Bjorge & Lang [2020] Public Law 508, 523-4):

(a)            Access to official documents: it should not be necessary for a select committee to seek an order or an address from the House in order to obtain documents from the government: Erskine May [38.32]. There is no plea of public interest immunity that may justify withholding documents form Parliament, including where those documents affect international relations or national security. It is for Parliament to find mechanisms to ensure that its committees can review sensitive material without imperilling those interests.

(b)            Ability of committees to ensure attendance of Ministers: Erskine May [38.34]. It should not be left to the discretion of Ministers to decide whether to attend to give evidence to a select committee, when the committee requires his or her attendance. This is a particular problem in a bicameral legislature, where the Minister is a member of the other House, an issue that could be addressed by the creation of a joint committee.

(c) Ministerial advisers are employed by the government to support their exercise of executive powers. They should have no more immunity from appearance before a select committee than any other public servant: HCL Report, 14.

I am happy to supplement these views by oral evidence (via video) should the Committee so wish.


3 June 2020