After a tumultuous twenty days of scrutiny, the House of Lords finally passed the European Union (Withdrawal) Bill last week. It now returns to the House of Commons, where MPs will have to decide whether to accept or reject the peers’ amendments. The upper house’s handling of the bill has generated considerable controversy among Brexiteers, and like the High Court judges who ruled against the Government on the Article 50 case, the Lords have been branded ‘enemies of the people.’ But these attacks are motivated by political animus rather than sound constitutional objections.
Peers made a number of significant changes to the EU (Withdrawal) Bill as it went through its parliamentary stages, including measures to:
- give Parliament a ‘meaningful’ vote on the outcome of Brexit negotiations;
- rein-in ministers’ use of ‘Henry VIII’ clauses;
- preserve the EU Charter of Fundamental Rights in retained EU law; and
- keep the United Kingdom in the EU customs union.
There is nothing inherently wrong with peers amending legislation. They are, after all, a revising chamber, and they are there to improve the quality of legislation. But many Brexiteers argue that the House went too far with its amendments and ended up violating the Salisbury-Addison Convention.
This Salisbury-Addison Convention (also known as the Salisbury Doctrine) was a gentlemen’s agreement struck in 1945 between the Labour Leader of the House of Lords, Viscount Addison, and the Conservative Leader of the Opposition, Viscount Cranborne (later the Marquess of Salisbury). At the time, the Tories had an enormous majority in the Lords, and they could easily obstruct Labour’s legislative program. Although the Labour Government would ultimately prevail thanks to the Parliament Act 1911, peers could still delay non-financial bills for up to two years (this period was later reduced to one year by the Parliament Act 1949). Naturally, Labour was keen to avoid these scorched-earth tactics, so Lord Addison and Lord Cranborne struck a deal whereby the Tories agreed that they wouldn’t obstruct the Government’s legislative program.
As Viscount Cranborne noted during the debate on the King’s Speech:
Whatever our personal views, we should frankly recognize that these proposals were put before the country at the recent General Election and that the people of this country, with full knowledge of these proposals, returned the Labour Party to power. The Government may, therefore, I think, fairly claim that they have a mandate to introduce these proposals. I believe that it would be constitutionally wrong, when the country has so recently expressed its view, for this House to oppose proposals which have been definitely put before the electorate.
But the Convention also prohibited wrecking amendments, as well. As Tory peer Lord Carrington noted in his memoirs:
The Lords should, if they saw fit, amend, but should not destroy or alter beyond recognition, any Bill on which the country had, by implication, given its verdict. The Lords, in other words, should not frustrate the will of the people.
What began as a gentlemen’s agreement between the Tory and Labour leaders in 1945 is now arguably a constitutional convention (however, the Liberal Democrats deny that it applies to them since they were not a party to the original agreement). But while the Convention seems clear-cut at first, the devil is in the details. What constitutes a manifesto bill? Which amendments would destroy a bill or alter it beyond recognition? The answers to these questions will always be highly subjective.
The debate over the Iron and Steel Bill of 1948-49 illustrates the difficulties that arise when one tries to translate the Salisbury-Addison Convention from theory into practice. Labour’s 1945 manifesto promised to nationalize the iron and steel industries, but Tory peers argued that the Iron and Steel Bill went beyond the Government’s manifesto commitment since it would nationalize companies that had nothing to do with the manufacture of steel. Furthermore, the Marquess of Salisbury noted that, while Labour won the largest number of votes in 1945, their manifesto was not backed by an overall majority of voters. Despite Tory concerns over the bill, they did not attempt to block it outright. Instead, they passed amendments that sought to delay nationalization from taking effect until after the next General Election, which would give the British people a chance to weigh-in on the Government’s proposals. In the end, ministers accepted the principle behind the peers’ amendments, and the bill became law.
Brexiteers may not like what the Lords have done to the EU (Withdrawal) Bill, but it’s a stretch to accuse peers of constitutional malfeasance. They didn’t reject the bill outright, and their amendments did not destroy the bill or alter it beyond all recognition. Britain can still leave the EU, even with peers’ amendments. It may not be the type of Brexit that Jacob Rees-Mogg and company would like to see, but they are not the sole arbiters of what Brexit should be. That is a question for Parliament, not a cabal of MPs.
If peers insist on their amendments after MPs have rejected them, then it would be fair to speak of a breach of the Salisbury-Addison Convention. But at this point, all the Lords have done is ask MPs to think again, and there is nothing unconstitutional about that.
 The House of Lords at this time was dominated by hereditary peers.
 HL Debates, 16 August 1945, col. 47.
 Lord Carrington, Reflections on Things Past: The Memoirs of Lord Carrington (London: Collins, 1988), 78.
 See the remarks of Viscount Swinton, HL Debates, 24 May 1949, col. 994.
 HL Debates, 29 June 1949, cols. 551-552.