It is now commonplace to observe that Brexit is putting the UK constitution under unbearable strain. One of the most obvious ways that it is doing so is by calling into question the allocation of powers between the Crown and parliament when it comes to dealing with the EU and, in due course, with other countries with which the UK will need to negotiate trade agreements after Brexit.
The traditional British model of making and implementing treaties is that they are negotiated and entered into by the Crown (i.e. the government) under the royal prerogative. Parliament has only two roles: it can pass a motion of no confidence in Her Majesty’s Government if it dislikes the treaty, or it can refuse to pass the legislation necessary to make the changes to domestic law that treaties usually require in order to be ratified. (In general, and in contrast to some other European countries, treaties have no effect in UK domestic law unless and until parliament changes the law.)
The problem is that the first option is not normally politically realistic and the second is unlikely to be attractive to MPs in the governing party once the government has concluded a treaty which, in most cases, cannot easily be re-negotiated: the treaty is at that stage effectively “take it or leave it,” and those MPs may well be reluctant to humiliate their government by telling it to leave it.
One recent innovation that was supposed to help was the Constitutional Reform and Governance Act 2010. That Act requires the government to lay treaties before parliament and gives parliament a power to delay ratification. But that limited power does not deal with the point that, by that stage, parliament is still being confronted with a “take it or leave it” choice.
In the 2017 Miller case, the Supreme Court was able to find an exception to the traditional model in the case of the Article 50 decision. It was able to interpret the European Communities Act 1972 as having, by implication, qualified the royal prerogative so that an Act of Parliament would be required before the Crown could serve a notice terminating EU membership. But Miller did not otherwise disturb the traditional model.
However, the view that the traditional model is unsatisfactory has been gaining ground. The heart of the problem is that international treaties concerning trade are far removed from the Cobden-Chevalier treaty (the 1860 tariff reduction treaty between the UK and Second Empire France). It is no longer a matter of negotiating tariff reductions on wine and agricultural produce in return for tariff reductions on manufactures in the course of a few lunches and an audience with the Emperor. Modern trade treaties are vast documents including very large numbers of commitments on sensitive matters of supposedly domestic policy, ranging from food standards to data protection to immigration rules to public procurement. If the Crown can simply produce one of these vast treaties at the end of a negotiating process and say to parliament “here it is: take it or leave it,” in a context where neither rejection nor amendment is realistic, then effectively parliament has handed over to the Crown the power to legislate in a vast range of areas.
Criticism of the traditional model is particularly powerful in the case of the biggest trade treaty of them all, namely the hoped-for EU withdrawal agreement and any subsequent deep and comprehensive free trade agreement with the EU.
“It can strengthen negotiators’ position if they have a clear duty to consult with parliament back home”It is therefore unsurprising that the debates on the Withdrawal Bill, and current debates on the Trade and Customs (Cross-border Trade) Bills, have seen attempts to tie the government’s hands, either by precluding it from entering into certain types of agreement (eg agreements making Northern Ireland a separate customs territory) or by forcing it to try to do so (eg to secure agreements to help unaccompanied child refugees join their families). In both the cases mentioned, the attempt was successful.
When it has objected to those attempts, the government has decried them as “unconstitutional.” That constitutional scrupulousness has not, however, stopped the government from departing from the traditional model in ways that weaken rather than strengthen parliamentary control. Thus, the Trade Bill would allow the government to amend domestic law in any way required by any treaties it negotiates with third countries to replace, for the UK, existing agreements between those countries and the EU.
That executive power to amend domestic law attenuates parliament’s traditional control over changes in domestic law required by treaties. The government claims that those treaties will not change anything and will simply “roll-over” the existing treaties: but that is unconvincing given the likelihood that those third countries will see their chance to demand further commitments from the UK.
But is there anything in the government’s claim that increasing parliament’s powers here would be unconstitutional? An international perspective helps. Although the United States Constitution firmly gives the President the sole power to negotiate treaties, subject only to ratification by the Senate, the reality is that US trade negotiations have to take place under cover of a trade promotion authority given by Congress. That authority is conditional on a range of goals being pursued in the negotiation (including an insistence on removing “unjustified” bans on, for example, GMOs and the infamous chlorine-washed chicken) and on complying with a range of procedures to ensure that congress is kept consulted. In the EU, the European Parliament is also consulted in considerable detail by the Commission as negotiations progress: and the Commission’s negotiating mandate is laid down by the member states.
All of this suggests that there is nothing intrinsic to the process of effective international negotiation that stops the legislature from setting out a clear negotiating mandate and being kept in the loop as negotiations proceed. Indeed, trade negotiators often point out that it can actually strengthen their position if they have a clear mandate and a clear duty to consult with their parliaments back home before making concessions: “I’d love to agree but as you know it’s outside my instructions/my client won’t let me” is, as any lawyer knows, often a good negotiating tactic.
“Trade today is far removed from the 1860 Cobden-Chevalier treaty between the UK and Second Empire France”Further, if your negotiating partner knows that a particular position is backed by a consensus back home, that may make it easier to negotiate, as both sides will have a realistic idea at the outset of what is achievable and can have confidence that concessions offered by the other side will be maintained. It is for those reasons that Stephen Harper—not the most instinctively consensual of Canada’s recent prime ministers—strongly advised the UK to seek a wide consensus before negotiating trade agreements (including, in particular, the agreement with the EU) and to keep consulting parliament and affected interests throughout the process. The government has to date largely ignored that advice in relation to its EU negotiations: but it was good advice.
There is obviously some need for decisions on negotiating stance to be made on the ground and for some details of negotiating strategy to be kept hidden: but the value of secrecy and “not revealing our hand” is in reality limited, and is in most cases a thin excuse for secrecy and unaccountability.
But the basic constitutional point is that parliament is sovereign, and the royal prerogative only survives in this area, as elsewhere, because parliament has let it. Against that background, it is hard to see any force in the prime minister’s claim that Dominic Grieve’s proposed amendment to the Withdrawal Bill (that would have given parliament a power to direct government negotiations to prevent a “no deal”) was unconstitutional. A sovereign parliament can take those powers if it wants to, and the experience of other countries shows that trade negotiations can be conducted effectively—even more effectively—when the legislature does take such powers. The fact that it has not been done before is not, even in the UK, a good reason for not doing it.
