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Parties, Parliament and the Brexit process: tensions facing parties, government and MPs


Richard Whitaker and Philip Lynch

The UK’s 2016 referendum vote to leave the EU has already heavily tested the cohesion of Parliamentary parties at Westminster. The UK’s relationship within the EU has long been a source of tension within and between parties, and Parliament is one of the primary arenas for contestation and division over the EU. The extent to which Parliament scrutinises the process of leaving the EU, and the effectiveness with which it does so, will be affected by internal party divisions, emerging cross-party alliances and the differing preferences of MPs. These preferences are affected by the conflicting pressures MPs face. Some are in constituencies where a majority voted a different way from the MP in the referendum and/or where the MPs won the seat by a very small number of votes. Some MPs hold different views to their party leadership on the EU issue. Furthermore, those hoping to achieve office on their party’s frontbench must toe the party line in order to increase their chances of achieving their personal aims. In what follows, we consider these intra-party tensions and the questions they have raised for representation and party cohesion at Westminster.

How have these tensions played out in parliamentary parties? Among Conservative MPs in government, a large proportion supported remain in the referendum. If we consider the 128 MPs who were in government at any ministerial level at some point during 2010-2017, almost three quarters (95) were remainers. Of the 27 MPs currently attending Cabinet, 20 supported remain in the referendum. From what we know of how and why political parties change, external shocks can constitute an important explanatory variable. The Brexit referendum is certainly such a shock and yet we still have a government which largely consists of those who supported remain in the referendum. The Conservative Party’s official position has therefore changed, but those in government are not so different (in terms of the leave versus remain balance), than those in place before the Brexit vote. Conservative MPs therefore appear to be lagging behind the change in party position. Nevertheless, we should add that the Parliamentary party has become more Eurosceptic over time. In addition, these differences between those in government, on one hand, and Conservative backbenchers, on the other, are not quite so stark as the figures might suggest. This is partly because MPs serving in Cabinet, of course, have to accept collective responsibility for its policies, which include delivering Brexit. Furthermore, we know from MPs’ public statements that some who supported remain, did so somewhat reluctantly.

Sticking with the Conservatives, how far have office-seeking goals affected MPs’ behaviour on Brexit? We can go some way towards answering this by looking at movements in and out of government and the extent to which MPs voted against the party line on EU issues. Of the 50 most rebellious Conservative MPs on EU issues during the 2010-16 period, only seven have gone on to some kind of government position under Theresa May’s premiership, including David Davies (Secretary of State for Exiting the EU), Chris Heaton-Harris, assistant whip and Andrew Percy, a junior minister in Communities and Local Government until the 2017 general election. Evidently, while Theresa May has placed some prominent leavers in key positions, more broadly, rebelliousness on EU votes has not been helpful for getting a foot on the government ladder in the post-referendum period.

What about the tension between MPs’ views and those of their constituents? If we consider Conservatives, there is no clear relationship between rebellion on EU issues in the 2010-16 period and estimates of the vote share for leave among an MP’s constituents (based on Hanretty’s estimates of this). The ten most rebellious Conservative MPs on the EU issue have range of leave vote percentages, with estimates ranging from only 39 per cent (Anne Main, St Albans) to 63 per cent for Peter Bone (Wellingborough).

Looking at all Labour and Conservative MPs and comparing the estimated majority vote in each constituency with each MP’s preference in the referendum, we find there were 308 constituencies (or 55 per cent) in which the MP voted a different way from the constituency majority. Note that the leave votes are estimates and might end up on the wrong side of 50 per cent for those cases where the differences between leave and remain were very small. We should therefore exercise some caution about the precise numbers here. With this caveat in mind, in 274 of these cases (or 89 per cent) where MPs and their constituents voted different ways, the MP supported remain while 50 per cent or more of the constituents voted leave. The proportion of MP-versus-constituency differences (in either direction) was higher for Labour MPs than for Conservatives. This leaves many MPs facing tensions between their own views and those of their constituents. Some have found this difficult to deal with. 47 Labour MPs (and one Conservative – Kenneth Clarke) defied their party whip by voting against the second reading of the bill granting the government authority to trigger article 50 of the Treaty on European Union (The European Union (Notification of Withdrawal) Act 2017), beginning the process of UK withdrawal. While most of these MPs voted consistently with their constituents, seven of these Labour rebels were in constituencies where a majority of those voting had opted for a ‘leave’ vote. Such members apparently took a trustee approach to representing their constituents, with most of these seven arguing via statements on their websites or speeches in the Commons, that while they acknowledge the referendum result, they do not believe that leaving the EU would be in their constituents’ interests. These differences between MPs and voters are particularly tricky to deal with in the context of declining trust in politicians and political institutions.

These sorts of tensions may have been a factor in the decision by a number of MPs to stand down at the 2017 general election. 12 of the 14 Labour MPs who did so faced a constituency with a different view to their own on Brexit, although most had healthy majorities. Eight of the 12 Conservatives stepping down faced a similar situation. Nevertheless, we should be cautious here as Brexit is likely to have been only one of a series of factors explaining these decisions not to stand.

Looking ahead to the agenda of the 2017-19 House of Commons session, party cohesion will be tested further as Parliament scrutinises the Repeal Bill, which will transfer EU legislation into UK law, and a series of bills dealing with particular policy areas currently dealt with by the EU, including immigration policy, one of the more contentious areas in negotiations between the UK its European partners. The strength of cross-party alliances as well as those within parties, will affect how bumpy or otherwise is the UK’s road out of the EU.