Questions of independence: What happens to Scottish MPs?

Of all the many uncertainties that would be created by a Scottish Yes vote on September 18th, none may be trickier than the position of Scottish MPs at Westminster. The challenges are both constitutional and political and could affect the legitimacy and viability of a UK government formed after next May’s general election. Could a majority or minority government headed by Ed Miliband have the authority to govern if it was dependent on Scottish Labour MPs who would be departing only a year or so later?

The referendum itself will in legal or constitutional terms not change the position of the 59 MPs from Scotland in Westminster at present. It starts a process of disengagement, and does not complete it. The MPs can only be removed by an act of the Westminster Parliament linked to the completion of a period of negotiations about how to separate Scotland from the present UK. So the MPs will remain at Westminster not just up to the general election but beyond it, since it is very unlikely that the negotiations will be completed by the end of next March when the Westminster parliament will be dissolved and election campaigning will start.

The real challenge is political. Whatever their legal rights, many English MPs and the press will see the Scottish MPs as different—a transitional group—from the day after the referendum if the vote is Yes. There will be pressure on them not to “interfere” in non-Scottish business.

A thorough report by the Lords Constitution Committee earlier this year said Scottish MPs should remain members of the Commons for as long as Scotland remains part of the UK. Until then, nothing would legally change and the Scottish MPs would be entitled to represent their constituents. But should they retain their current rights? Should they be permitted to vote on non-Scottish issues? Or, should they recuse themselves and some type of formal limit be introduced immediately? And should Scottish MPs be involved in the negotiations and in subsequent debates on legislation to bring in independence?

What's more, the 59 Scottish MPs could determine who forms the next government. In 2010, 41 of the Scottish MPs were from Labour, 11 Liberal Democrat, six from the Scottish National Party, and one from the Conservatives. Labour has relied heavily on support from Scotland for a long time. However, in only two general elections since 1945 would the largest party have been different if Scottish MPs had been excluded—1964 and February 1974. But, in October 1974 and 2010, Scottish MPs made the difference between a minority and a majority administration. The balance is all in one direction, benefiting Labour and working against the Conservatives.

Any suggestion that a Labour government would depend either for a majority, or to be the largest single party, on Scottish MPs would be explosive. Such a government’s authority and ability to carry controversial legislation would be in question from the start whatever the law says. You can easily imagine the approach of The Sun and the Daily Mail, not least with a controversy about an in/out European referendum around as well.

It will be impossible for party leaders to continue to describe such questions as hypothetical. If there is a Yes vote—and the odds are still against—answers will have to be produced on what happens to the 59 Scottish MPs within weeks at most.

Peter Riddell is director of the Institute for Government