The announcement of Lord Frost’s role brings some much-needed (although not complete) clarity about Whitehall arrangements for the future management of the UK’s relationship with the EU that will be welcome in Parliament. Such clarification is a necessary (but not sufficient) condition for the House of Commons, in particular, to make more progress in developing arrangements for the scrutiny of the UK’s new EU relationship. (With respect certainly to select committees, the House of Lords is further advanced in this process.)

Since the post-Brexit transition period ended on 31 December 2020, there has been uncertainty among MPs (as well as external observers and stakeholders) in particular about the extent to which the Department for International Trade (DIT) might have responsibility for UK-EU trade matters. The issue was highlighted on 15 February when Emily Thornberry MP, Shadow International Trade Secretary, let it be known that questions on UK-EU trade issues tabled for the next session of DIT questions in the House of Commons on 25 February had been diverted to other departments. However, the matter had first came to the fore in the Commons during the previous set of DIT questions, on 14 January, when Ministers answered some questions on UK-EU trade but suggested that others were better addressed to the Cabinet Office. The exchanges prompted Ms Thornberry to table a written question and the International Trade Committee (ITC) to write to International Trade Secretary Liz Truss, both trying to establish who had responsibility for UK-EU trade matters.

The press release on Lord Frost’s appointment confirms that the new Minister, in the Cabinet Office, will be in the lead across all aspects of the future UK-EU relationship, including trade.

This is in line with the fact that, as stated in the reply to Ms Thornberry’s question, the TCA “covers a wide range of areas and is the responsibility of various departments”. Lord Frost’s role also perpetuates the much older UK position that, given the wide range of policy areas in which the EU is engaged, management of the UK’s EU relationship requires a cross-government coordination function that is best discharged in the Cabinet Office. Having the Cabinet Office in the central role is particularly appropriate now that relations between the UK government and the devolved nations and administrations, especially in Northern Ireland, are engaged by UK-EU relations in a more complex and delicate way than they were pre-Brexit.

The new arrangements in government for the management of EU-related matters raise two issues for parliamentary scrutiny, namely:

• House of Commons scrutiny of a House of Lords Cabinet Minister; and

• for EU-related matters, the role of the Cabinet Office in relation to other departments.

Of the two, the more certain and more serious challenge for Parliament arises from the fact that Lord Frost is not a member of the House of Commons.

As a Minister in the House of Lords, under current parliamentary arrangements he cannot speak in the Commons – to make statements, answer questions or participate in debates.

Apart from the brief three-month period when Baroness Morgan retained her position as Culture Secretary after being appointed to the Lords (pending the full formation of Boris Johnson’s new government after the December 2019 general election), the last time when there was a Cabinet Minister with policy responsibilities in the House of Lords was before the 2010 election: Lord Mandelson was Business Secretary and Lord Adonis Transport Secretary in 2008-10 and 2009-10, respectively.

Those appointments stimulated renewed discussion – and Commons Procedure Committee recommendations – about having Lords Cabinet Ministers appear before the Commons in some way, but in the end no such innovation was made in the elected House before the 2010 election. By contrast, the House of Lords introduced a question time for Secretaries of State who were Members of the House, and this practice was briefly revived in January 2020 for Baroness Morgan.

One immediate issue is that there might be a delay before Lord Frost could participate in proceedings even in the Lords, because since 9 September 2020 he has leave of absence from the House for the rest of the Parliament. Under Standing Order No. 22, a Member who has been granted leave of absence should not attend sittings of the House; and should s/he wish to do so, should give three months’ notice. In the current case, the three-month period might be shortened if the next parliamentary session were to start before it expires, because the Lords agreed in October 2020 to change its Standing Orders so that leave of absence is granted until the end of a session rather than a Parliament, and it appears that the change will apply retrospectively to Members granted leave before it was made.

Assuming that arrangements are put in place to allow Lord Frost to face questions from the House of Lords, this will not resolve the problem in the Commons.

Normally, when a department has a Minister in the Lords, its other Ministers who sit in the Commons handle his or her departmental business there. However, owing to the widely varying policy areas they cover, Cabinet Office Ministers may be less able to cover each others’ briefs than is the case in other departments. In the present instance, Commons handling of Cabinet Office EU business would fall to Michael Gove (depending on his role following Lord Frost’s elevation) and/or Paymaster General Penny Mordaunt MP, whose current official job description includes supporting Mr Gove on some EU-related matters, and who has appeared on EU issues both in the House and before select committees. If no alternative arrangements are made for Lord Frost to appear before the Commons, the need for a Commons Cabinet Office line-up that is able to handle EU-related business could be a constraint on any future government reshuffle.

Even if Mr Gove and/or Ms Mordaunt handle Cabinet Office EU-related business in the Commons, Lord Frost’s appointment to replace Mr Gove as Co-Chair of the UK-EU Joint Committee and Partnership Council means that, as things stand, the full elected House will lose direct access to the Minister representing the UK in these powerful decision-making bodies.

This will come on top of the ending of routine UK-EU engagement at head of government level: the TCA does not provide for UK-EU summits. Other things being equal, this means that there will be fewer prime ministerial appearances in the Commons than there were before 2021 (because the Prime Minister will no longer make statements after European Council meetings or head-of-government-level Brexit negotiations); and those prime ministerial appearances that do take place will no longer be those of a Minister personally taking part in routine formal engagement with the EU.

Following Lord Frost’s appointment, the House of Commons should again consider how Cabinet Ministers in the House of Lords could appear before it, so that it retains direct scrutiny of the Minister representing the UK at the highest level of routine formal UK-EU engagement.

As things stand, select committee work will be the main means by which the House of Commons can hold Lord Frost to account.

House of Commons select committees cannot formally summon Members of the House of Lords to attend, but the Upper House has given standing permission to its Members to appear (by Standing Order No. 24), and the process is not normally problematic. As things stand, Lord Frost would be most likely to appear before the European Scrutiny Committee, which has by default become the House of Commons' only dedicated EU-focused select committee.

The second set of issues raised by Lord Frost’s appointment are more familiar ones, of inter-departmental boundary-drawing – although it remains relatively rare for the Cabinet Office to have a Cabinet-level Minister with a major, single and lead policy brief; and the ministerial lead on EU matters has only sat within the Cabinet Office for a year, since the abolition of the Department for Exiting the EU (DExEU).

For Parliament, the overarching question is whether the arrival of a new lead Minister, the re-making of this job (compared with Mr Gove’s) to deal only with EU matters, and confirmation that the government’s EU policy lead will sit on a more settled basis in the Cabinet Office (as opposed to another department), might change the parliamentary scrutiny practices developed in the last year under Mr Gove.

In particular, parliamentary scrutiny will be affected by the extent to which other departments and their Ministers will continue to be willing and able to answer on EU-related matters within their policy areas.

This is likely to continue to vary between departments. The greatest potential for overlap and need for close coordination seems to lie between Lord Frost and the two internationally-focused departments that remain, DIT and the Foreign, Commonwealth and Development Office (FCDO). Against the background of the questions raised by Emily Thornberry and the ITC, Lord Frost’s job description seems to confirm that he will lead on UK-EU trade matters, keeping DIT’s responsibilities for trade agreements to those outside the EU. For select committees, the issue of inter-departmental boundaries arises especially in the Commons, because its select committee system is department-based, and further clarification of who in government is doing what may take place through select committee work. For example, will a Cabinet Office or DIT Minister (or both) give evidence to ITC’s new inquiry into the UK-EU trade relationship?

If departments were to start referring all questions about EU-related matters to Lord Frost and the Cabinet Office, it could risk creating practically impossible demands on Lord Frost (and perhaps Ms Mordaunt) for select committee appearances, and reversing the ‘mainstreaming’ of EU-related issues that has taken place across the House of Commons since 2016. This scenario is unlikely, given other departments’ ongoing interests in EU-related matters, capacity constraints in the Cabinet Office, and long-established Whitehall habits of the Cabinet Office operating as a hub. However, departmental Ministers’ ability to face scrutiny on UK-EU matters will depend in part on the openness of the cross-government processes that are taken forward by Lord Frost in his new role.

The extent to which EU-related matters are directed to the Cabinet Office, or instead continue to be handled by other departments too, could also affect departmental question times in the Commons Chamber. At present, Cabinet Office questions take place roughly every five sitting weeks, as for other departments. Depending on the extent to which these might become the only opportunity for MPs to question Ministers on UK-EU matters, these sessions might come to be seen as too few. In this context, it is notable that Alok Sharma MP, in his new standalone Cabinet Office role of COP26 President, has been given his own question time on 24 February, presumably as the first of what will become a series. Might the House want to consider a standalone question time for UK-EU matters?