Whichever Conservative candidate becomes Prime Minister on 6 September, all the indications to date suggest that there will be some kind of 'fiscal event' during the planned short September sitting, most probably on 14 or 21 September. The form that this 'event' will take - an emergency Budget (or mini-Budget) or a financial statement - is not yet clear.

Parliamentary authorisation for proposals to raise revenue or spend money will be required in the form of primary legislation. Tax-raising measures or other changes to tax provisions require Ways and Means Resolutions. In a normal financial cycle, expenditure is authorised via the Estimates process. Additional new expenditure outside this process requires a Money Resolution. If the fiscal event is a Budget rather than an emergency financial statement, the relevant Bill will take the form of a Finance Bill.

Erskine May, the authoritative guide to parliamentary practice, states that the House of Commons' agreement to the imposition of taxation or to expenditure plans "should be conditional upon a number of distinct opportunities for discussion". And when a Bill is introduced on the basis of Ways and Means Resolutions, the usual practice is that no more than one stage of the Bill can be taken on the same day. However, these principles and practices may come into conflict with the need for rapid action to tackle the economic emergency.

If there is a Budget, it is normal practice for the proposals set out in the Chancellor's statement to be debated for four days afterwards, though this need not be successive days immediately after the Budget statement. If a Budget were to be held on 21 September, this would nonetheless have implications for the conference recess, as the House of Commons is due to rise the following day.

There are precedents if the Government wants to accelerate the passage of its legislation. For example, the Health and Social Care Levy Bill went through all its Commons stages in one day in September 2021. There are also precedents for giving Finance Bills an accelerated passage following a Budget (though usually in advance of an imminent General Election).

However, a Finance Bill may not need to be treated as emergency legislation. Temporary authority is granted for any changes to taxes and duties that the Government proposes should take effect on Budget day or soon after via a Provisional Collection of Taxes resolution which is agreed after the Budget statement. This parliamentary authorisation remains valid for seven months, provided that the Second Reading of the Finance Bill takes place within 30 sitting days.

Control of taxation can only be exercised by the House of Commons, and the role of the House of Lords is "to agree, and not to initiate or amend". Normal practice for a Bill of 'aid or supply' (a Bill that authorises taxation or expenditure of money) is that a Second Reading stage is held in the House of Lords, but there is no Committee stage (in procedural terms it is 'negatived') and Report Stage and Third Reading are thus formalities.

However, the House of Lords is due to rise for the conference recess on 15 September and return on 10 October. So, depending on the form that the 'fiscal event' takes, and on the day on which it is held, Peers may need to alter their recess arrangements if they are required to sit for a Second Reading between these dates. The Government may also decide to cancel or reduce the planned three-week party conference recess (23 September to 16 October) for the House of Commons.

The new Government will inherit a legislative programme that is already heavy and that includes a number of technically complex and politically controversial Bills. Several measures have the potential to expose differences within the parliamentary Conservative party and could need deft handling if they are to help bring the party back together, rather than exacerbate divisions. This could be a challenge in particular for new Ministers who must pick up pieces of legislation that are already in train.

If, in trying to establish its political identity, the Government seeks to amend Bills that have already started their parliamentary process, it risks having wasted parliamentarians’ time and efforts. The introduction of amendments after the parliamentary process has started, reducing the opportunity for scrutiny of new provisions, will further aggravate parliamentary relations.

If the Government adds new Bills to the legislative programme, scrutiny time in the remainder of the 2022-23 Session will come under further pressure.

Among the 23 Government Bills on which parliamentary proceedings are underway, media reporting suggests that the most likely targets for possible amendment by the new Government include:

• the Financial Services and Markets Bill and the Bill of Rights Bill (neither of which have yet even had their Second Readings, which are scheduled for 7 and 12 September, respectively);

• the Levelling-up and Regeneration Bill (which, if Greg Clark MP leaves Government again, will have had three Secretaries of State during its Committee stage alone); and

• the Online Safety Bill (which, on current plans, will have the first day of its Report Stage under the Johnson Government and the second under its successor).

Of the Bills foreseen in the May 2022 Queen’s Speech, 11 have not yet been introduced. Several of these are also potentially controversial within the parliamentary Conservative party, including:

• the Conversion Therapy Bill;

• the Economic Crime and Corporate Transparency Bill (effectively part two of the Economic Crime (Transparency and Enforcement) Act 2022);

• the Media Bill (on the privatisation of Channel 4);

• the Renters Reform Bill; and

• the Transport Bill (which is planned to enact a major overhaul of the railway sector via the creation of Great British Railways).

In January 2022 the Government announced that it would bring forward a Bill to "make it easier to amend or remove outdated 'retained EU law' - legacy EU law kept on the statute book after Brexit as a bridging measure". The Bill was to be accompanied by a cross-government exercise to identify where Retained EU Law (REUL) was to be reformed, repealed and replaced in favour of exclusively UK-tailored regulation.

The Bill was expected before the Summer recess in 2022 but did not arrive, with the proposed sunset clause in the Bill - which would determine when REUL would fall - apparently the subject of inter-departmental dispute. The Minister responsible for the Bill, Brexit Opportunities Minister Jacob Rees-Mogg MP, reportedly proposed a sunset of June 2026. Departments such as DEFRA, that will have significant swathes of REUL to deal with before the sunset, reportedly wanted a deadline of 2028. However, during the Conservative leadership campaign over Summer 2022, Ms Truss promised that the sunset for all EU-derived laws would be within 15 months – that is, by the end of 2023. Her rival, Mr Sunak, promised that REUL would be removed from the statute book by the time of the next General Election – that is, by January 2025 at the latest. How quickly the Bill emerges after Parliament returns in September 2022 will thus depend on if and when these differences can be reconciled and a sunset target agreed.

Once the Bill is introduced to Parliament, there will be considerable pressure to get it through as quickly as possible, not least to maximise the amount of time available to use the powers prior to the sunset deadline. The Bill will likely be subject to greatest challenge in the House of Lords, where Peers will be concerned about the scope of the delegated powers to be granted to Ministers to make changes to REUL.

However, Mr Rees-Mogg has indicated an ambition to use the Legislative Reform Order (LRO) scrutiny process as a "key tool" in the amendment of REUL. If this proposal makes it into the final Bill, it will provide a greater role for Parliament in the scrutiny and approval of some changes to REUL compared to the standard scrutiny procedures. This might smooth the Bill's passage considerably.

The Northern Ireland Protocol (NIP) Bill completed its Commons stages just before the Summer break without amendment and more quickly than initially planned. It is set to form a major part of the House of Lords' legislative work in Autumn 2022, although no date for its Second Reading there has yet been announced.

One set of issues around the Bill concern the speed with which it proceeds. These are part of a multi-way tussle between the UK Government, the EU and the Democratic Unionist Party (DUP) in Northern Ireland. As the Minister responsible for the Bill, Ms Truss may be keener than Mr Sunak for the Bill to proceed, and quickly, if she were to become Prime Minister. However, she may also be more likely to invoke Article 16 of the Northern Ireland Protocol, which might hold the Bill process back.

A second set of issues concerns the Bill's domestic constitutional politics at Westminster. The Bill runs to just 26 clauses but 17 of these confer significant powers on UK Ministers to make new domestic law in place of provisions of the Northern Ireland Protocol that are disapplied by the Bill. The skeleton nature of the Bill means that the real operation and implementation of its policy objectives will be entirely at the discretion of Ministers once it receives Royal Assent. Peers will want to tighten up the wording of the Bill and restrict ministerial discretion to legislate by Statutory Instruments in areas such as NIP-relevant customs and trade policy without the need for active parliamentary approval. Tension may arise over the amount of time that the Lords are likely to want to scrutinise the Bill in detail, against the Government's desire to get it on the statute book as quickly as possible.

However, fundamental constitutional questions are also at stake, and what happens with the Bill will depend on the parliamentary tactics adopted by different political groups within the Lords. Peers are not whipped like MPs, and opposition to the Bill is widespread, including on the Conservative benches. The independent crossbenchers hold considerable influence, but lack the numbers to determine an outcome on their own; the position adopted by Labour may therefore be critical.

If Peers believe that the Bill's provisions would break international law, their concern for this constitutional principle will come into conflict with their respect for the wider constitutional tenet that the unelected House should ultimately defer to the elected. For many Peers it will be a matter of personal – and in some cases professional – principle that they not put themselves in the position of being party to law-breaking. It cannot be ruled out that the House of Lords ultimately fails to agree to the Bill, after which a constitutional crisis may ensue.

The first skirmish will be at Second Reading: will Peers reject the Bill outright at this stage, or will they let it proceed to the amending stages and 'ping-pong', in the hope that the Government cedes some ground and/or that the development of negotiations with the EU obviates the need for the Bill at all?

Autumn 2022 will see the first meeting in the UK of the UK-EU Parliamentary Partnership Assembly (PPA), the new inter-parliamentary body between the UK and European Parliaments which is set up under the two sides' Trade and Cooperation Agreement (TCA). The meeting (which is most likely to take place in the first week of November) will be the second for the new body, after it held its inaugural session in Brussels in May 2022.

With up to 35 Members participating from each side, the event – which will probably be held over two days – is potentially quite a large one, once officials and interpreters are also taken into account. The degree of political attention drawn by the meeting will depend partly on whether it is addressed by the Foreign Secretary (who will presumably still have ultimate responsibility for UK-EU relations under the Truss or Sunak Governments and who, in the form of Ms Truss, did not address the May meeting, although this may have reflected a G7 scheduling clash).

For PPA-watchers, a key issue will be whether the Assembly exercises its power to make recommendations. (It could not do this at its May meeting because it only agreed its Rules of Procedure, under which this process would take place, on that occasion.) Steps on the possible setting-up of working group-type arrangements, to help overcome the limitations imposed by the fact that the full PPA meets only twice a year, may also be worth looking out for.

In broader terms, the November meeting will be a test of the extent to which such inter-parliamentary contacts can help ease international relations. In the context of post-2016 UK-EU relations, the May meeting was notably constructive, a testy opening session with Paymaster General Michael Ellis MP and European Commission Vice-President Maroš Šefčovič notwithstanding. However, in Autumn 2022, UK-EU relations look set to be even more difficult, with each side (not just the EU) in the early stages of formal dispute proceedings against the other, and the PPA meeting possibly coinciding with Lords consideration of the NIP Bill.

The holding of a PPA meeting in London may also bring into sharper focus the question of where the Assembly fits in the UK system for parliamentary scrutiny of post-Brexit UK-EU relations. As of Autumn 2022, the system – certainly in the Commons – has been driven mainly by inertia, with the European Scrutiny Committee (ESC) emerging as the key scrutiny body by default.

There may be results early in the Autumn from negotiations between the Cabinet Office and the ESC (and its counterpart in the Lords) about the details of the way in which the pre-Brexit system is adapted for the post-Brexit era (although the transition to the Truss or Sunak Government might delay this). However, any new arrangements would be put fully to the test only when the UK-EU Partnership Council next meets; given that the body "shall meet […] at least once a year" under the TCA and held so far its only meeting in June 2021, this should take place before the end of 2022.

Among parliamentary scrutiny issues where parliamentarians will be looking to the Truss or Sunak Government for an improvement in performance, the scrutiny of free trade agreements (FTAs) offers a potentially early and high-profile opportunity to do things better.

The formal Commons scrutiny process for the UK's first new post-Brexit FTA, with Australia, ended just before the Summer in a row with the Government (generating an Urgent Question) and an embarrassment for the House. The statutory pre-ratification scrutiny period for the FTA under the Constitutional Reform and Governance Act 2010 (CRAG Act) came and went without the elected House having debated the Agreement, despite the Commons' International Trade Committee (ITC) having recommended that a debate be held, and despite the Government saying that it would "seek to facilitate" a debate in such circumstances. However, the Government said that in this case no parliamentary time could be found. In terms of the CRAG Act process, the Government has been able to ratify the Australia FTA since 21 July.

The underlying problem, in part, is that for many UK FTAs there are now 'add-ons' before the CRAG Act process, in the shape of the requirements on the Government under Section 42 of the Agriculture Act 2020 to lay a report on an FTA's impact on UK statutory protections for health, animal welfare and the environment, before triggering the CRAG Act scrutiny period; and to commission and receive advice from the Trade and Agriculture Commission (TAC) before doing so (under Section 9 of the Trade Act 2021, although this provision has not yet been commenced.) During the process for the Australia FTA, the Government and the Commons ITC were in effect negotiating in real time about where the timings of these steps should fit in relation to the CRAG Act process, and, more broadly, about what the scope of the ITC's scrutiny should be in light of these additions. The ITC took a 'maximalist' approach, wishing to have good time to scrutinise not only the FTA text but also the TAC and Section 42 reports, and take evidence from the Secretary of State, before the CRAG Act scrutiny period was triggered. In this context, the Australia process was further hampered by repeated difficulties in securing the Secretary of State's appearance before the Committee.

The failures of the Australia process explain the importance of the CRAG Act process for the UK's second new post-Brexit FTA, with New Zealand, which is expected to take place during Autumn 2022. The shortcomings of the Australia process might be forgiven because it was the first use of the UK's new provisions; but if the ITC (as it almost certainly will) recommends a debate on the New Zealand FTA and again none takes place within the CRAG Act period, this may start to become normalised. The preconditions for a smoother process for the New Zealand FTA are in place, with the Government having laid its Section 42 report on the last sitting day before the Summer and the ITC having already taken evidence from the Secretary of State.

The row over CRAG Act-related timings is in any case a row only about the mechanics of a very weak form of parliamentary involvement in the making of new FTAs. The Government proposes that any pre-ratification debate in the Commons be held on a neutral (that is, unamendable) motion, so there would be no way for the House to use the debate to resolve against ratification under the CRAG Act, even if it wanted to. The Government's adherence to holding only such procedurally-inconsequential general debates is why it remains possible (although unlikely) that it could still schedule a debate on the Australia FTA during the Autumn. The Government will not ratify the Australia FTA until the Trade (Australia and New Zealand) Bill, which is needed to implement the Agreement in domestic law and which is due to have its Second Reading in the Commons on 6 September, has achieved Royal Assent later in the Autumn.

Select Committees will have had a curious quasi-interregnum since the mass ministerial resignations of early July, with little time but also – given the likelihood of a further major reshuffle under the new Prime Minister – often little incentive to start developing constructive relationships with new Ministers appointed at that time. The knowledge that there would be a new Prime Minister on the second sitting day after the Summer may have hampered the kind of planning and preparatory work that Select Committee Members and staff often undertake during the long adjournment, with possible effects seen into the Autumn.

The advent of the Truss or Sunak Government could affect Select Committees in three ways:

i) Scrutiny topics. Changes may be required to Select Committee work plans, if the Government under the new Prime Minister announces new initiatives that require scrutiny (such as any revision of the 2021 Integrated Review of Security, Defence, Development and Foreign Policy), or makes changes that render current work already outdated.

ii) Machinery of Government. Primarily in the Commons, where the departmental Select Committees take on the remits of 'their' departments, machinery-of-Government changes have knock-on effects for Select Committee activities and responsibilities. Potential machinery-of-Government issues worth looking out for in the current case include:

• whether the Cabinet Office (CO) retains a dedicated Brexit-related Minister (such as Jacob Rees-Mogg currently, or Lord Frost previously), or instead sees its Brexit-related work placed under the responsibility of a CO Minister with a more general remit;

• whether the responsibilities of Michael Gove MP as Minister for inter-governmental relations, which he took with him from the Cabinet Office to the Department for Levelling Up, Housing and Communities, stay there or are migrated back.

iii) Personnel. The potential naming of current Select Committee Members to Government will require the appointment of replacements, potentially including Chairs – most obviously, at the Commons Foreign Affairs Committee (FAC), if current Chair and ex-Conservative leadership contender Tom Tugendhat MP enters Government.

For his part, if Greg Clark leaves Government again and would like to resume his previous job as Chair of the Commons Science and Technology Committee (which does not appear to have named an acting chair with effect beyond the start of the Summer break), nominations close only on 13 September, so he would have time to stand.

Meanwhile, former Ministers returning to the backbenches could constitute a pool of relatively well-informed new Select Committee Members.

Machinery-of-Government and/or Government personnel changes might also prompt a reshuffle on the Labour frontbench, which could also mean Members leaving Select Committees and requiring replacement.

The inquiry of the House of Commons Privileges Committee into whether Boris Johnson's statements in the House of Commons about parties in Downing Street amount to a 'contempt of the House' will begin in earnest once Parliament returns in September. There is no formal deadline for the inquiry to report.

An early matter to be resolved will concern the Committee's membership. The Committee, which has a government majority, is comprised of seven MPs: four Conservatives, two Labour and one SNP. However, the Conservative Laura Farris MP has said that she stepped down from the Committee prior to the Summer recess. She remains listed as a Member on the Committee's website (as of 1 September), and formally an MP remains a member of a Committee until the Committee of Selection nominates a replacement and the House endorses this nomination.

Normally, a motion to appoint a Select Committee Member is a formality. However, throughout the Summer, Members of the Committee have been accused, including by Cabinet Ministers, of engaging in a 'witch hunt' against Boris Johnson. The Prime Minister recently commissioned legal advice about the conduct of the inquiry which has since been selectively leaked to the media in a way that appears to be designed to discredit the inquiry. In this toxic atmosphere, it would be understandable if no Conservative MPs wished to join the Committee. There may also be a risk that the process to name a replacement may be contested by fellow Conservative backbenchers, in a bid to damage the inquiry.

As Sir Ernest Ryder, legal adviser to the Committee, made clear in an article during the Summer adjournment, the Privileges Committee itself cannot unilaterally stop the inquiry. Unlike most other Select Committees, it "cannot act of its own volition but instead takes the terms of reference for its inquiries from Resolutions of the House". The inquiry can therefore only be stopped if the Government brings forward a motion to rescind the Resolution of the House that MPs agreed on 21 April (which referred the Prime Minister's conduct to the Committee and asked it to investigate) and MPs then vote to support that new motion.

The likely appearance of Boris Johnson to give oral evidence before the Committee will be eagerly awaited. He, like other witnesses appearing before the inquiry, "may be accompanied by a legal or other adviser and may take advice from them during the session". Oral evidence will be taken on oath and any written evidence will require an accompanying 'statement of truth'.

But when the Committee finally reports to the House that will not be the last word on the matter. If it finds that "on the balance of probabilities" the former Prime Minister's conduct did amount to a 'contempt of the House' then it can recommend one or more of a wide range of potential sanctions, taking into account "the degree of personal knowledge and intention that is demonstrated". However, if will then be for the whole House to decide what, if anything, to do in response to the Committee's findings and recommendations. The prospect of the former Prime Minister being suspended from the House, let alone recalled (if the suspension were for 10 sitting or 14 calendar days), is at the very upper end of the potential range of sanctions.

On 22 June 2022 the House of Commons agreed a motion to establish a Speaker's Conference to "consider and make recommendations upon the contractual arrangements for the employment of Members' staff". The body was set up at the Speaker's instigation to consider ways in which the working culture of the Commons could be improved through "a more inclusive and respectful working environment", following months of damaging accusations about bullying and harassment of staff by MPs.

On 25 July 2022 the Speaker wrote to all MPs and their staff setting out the issues that would be considered. The Conference will explore the challenges and benefits that arise from MPs directly employing their own staff, and consider whether contractual changes and changes to the support provided to MPs and their staff by the Commons authorities could deliver improved support for Members and Members' staff.

The Conference will be chaired by the Speaker and comprise 14 other Members drawn from across the Commons and reflecting the party balance in the House. The Speaker indicated in his letter of 25 July that Members of the Committee would be appointed shortly after the Summer recess. Unlike the last Speaker's Conference (in 2008), this one has been established as a Committee of the House of Commons, with the powers and legal protections that that entails. As the Clerk of the House explained in a memorandum to MPs, "This will ensure that it can secure any evidence it needs, and that evidence can be given to it freely". The Conference can run until the end of the Parliament, but it is required to produce a first report to the House by the end of October 2022, which must address the principles that will underpin its work.

Although this Inquiry has thus far flown under the radar compared to the more high-profile Privileges Committee inquiry, it could also prove contentious. MPs are currently responsible for the employment of their own staff but the Conference will consider whether this remains appropriate. Many MPs will be concerned about any proposal that may undermine their right to determine the staffing of their own offices. But if the Conference's evidence sessions bring to the fore further damaging cases of bullying and serious harassment of staff, then the reputation of MPs and the House of Commons will be further impaired.

Given the state of the economy, cost concerns about the Restoration and Renewal (R&R) project for the Palace of Westminster will become even more acute from Autumn 2022 - just at a time when arrangements around planning and governance for the project have been put almost back to square one, and key decisions must (still and again) be taken.

Concerns about the cost of the project, mainly among Conservative MPs (on both the front- and backbenches), have been among the key drivers of the near-reversal of previous arrangements surrounding R&R that has taken place since the 2019 General Election.

In July 2022, both Houses agreed resolutions backing a joint proposal from the Commissions of the Commons and Lords to abolish the independent Sponsor Body which had been established under the Parliamentary Buildings (Restoration and Renewal) Act 2019 to manage the R&R project, and instead to bring management of the project in-house, within Parliament. (This applies at least during the immediate ‘programme definition’ – as opposed to delivery – phase of the project.) More specifically, the Sponsor Body’s statutory functions are formally to be transferred to the Clerk of the House of Commons and his equivalent, the Clerk of the Parliaments, in the Lords (as the Corporate Officers of the two Houses), and the Sponsor Body’s work is to be carried out by a new joint department of the two Houses (established under the Parliament (Joint Departments) Act 2007). Governance of the R&R project is to take place through a new two-tier structure, comprising:

• the Commissions of the two Houses jointly re-constituted for these purposes as a single Client Board; and

• a Programme Board, which will enjoy delegated authority from the Commissions, include external members, and looks set to be the critical body shaping the future of the project.

During Autumn 2022, the Government is expected to bring forward the Statutory Instrument (SI) which is required under the 2019 Act to abolish the Sponsor Body and effect the transfer of its functions; the SI will need the approval of both Houses. Progress towards the potentially critical appointment of the Programme Board will be a key item for R&R-watchers during the Autumn – although exactly how the Board is to be appointed, and the balance on it between Members, parliamentary staff and external figures, are not yet clear.

Meanwhile, six years after a Joint Committee of the two Houses first agreed a way ahead for R&R (and envisaged the works on the Palace beginning in 2023), and four years after both Houses agreed to vacate the Palace simultaneously during the works (‘full decant’), the restructured project must still develop a range of options for R&R’s scope and implementation. It is planned that these will be presented to the two Houses in 2023, although 'before the Summer' of that year was the target date before the 2022 governance overhaul.

The economic crisis will presumably generate further pressures to keep the overall costs of the project down; but it could (and should) also generate greater consistency about cost reductions across the various elements of the project: it is inconsistent to wish to downgrade, on cost grounds, the specifications for temporary accommodation and for the post-R&R Palace, while simultaneously resisting ‘full decant’ during the works, since all studies have shown that this is the lowest-cost option for delivering the essential repairs to the Palace, which make up by far the greatest share of the total costs.

Fowler, B. & Fox, R. (2022), 10 things to look our for in Parliament in Autumn 2022 (Hansard Society: London)