The Terminally Ill Adults (End of Life) Bill (“the assisted dying bill”) — a Private Member’s Bill (PMB) to legalise assisted dying in England and Wales — failed to complete its passage through the House of Lords before the end of the 2024–26 parliamentary session.

Supporters are therefore expected to seek the bill’s reintroduction in the next session, with the possibility of using the Parliament Act 1911 to override continued opposition in the Lords.

The Parliament Act permits the House of Commons, in limited circumstances, to present legislation for Royal Assent without the consent of the House of Lords.

Since 1911, the procedure has been used only seven times, and never for a Private Member’s Bill. If it were to be used for the assisted dying bill, novel procedural adaptations might be required.

Section 2 of the Parliament Act 1911 sets out the procedural conditions that must be met if a bill is to be presented for Royal Assent without the House of Lords consent.

• The bill must have been sent to the House of Lords at least one month before the end of the first session.

• The House of Lords must have “rejected” the bill in the first session. “Rejection” means either: defeat at Second or Third Reading; failure to complete all stages before the end of the session; or insistence on Lords amendments unacceptable to the Commons.

• At least one year must elapse between Second Reading in the House of Commons in the first session and Third Reading in the Commons in the second session.

• The bill introduced in the Commons in the second session must be “identical” to that sent to the Lords in the first session. There are some limited exceptions: changes required because of the passage of time; and inclusion of Lords amendments agreed in the first session. In addition, the bill sent for Royal Assent may also include Lords amendments agreed in the second session, as well as any “suggested amendments” proposed by the Commons and agreed by the Lords.

• The “identical” bill must be sent to the House of Lords at least one month before the end of the second session. Whether this requirement can be satisfied will depend on the speed of proceedings in the House of Commons. A session beginning in May 2026 would ordinarily be expected to last around 12 months, although the precise timetable remains flexible.

• The House of Lords must again “reject” the bill in the second session. The meaning of “rejection” is the same as in the first session. However, if the Lords ultimately pass the bill in the conventional manner, the Parliament Act procedure would not be required.

• Once it becomes clear that the House of Lords will not pass the bill, the Speaker of the House of Commons must certify that the statutory conditions for use of the Parliament Act have been satisfied before the bill may receive Royal Assent.

If MPs give an identical assisted dying bill a Second Reading in the 2026–27 Session, that will signal the Commons’ intention to proceed, if necessary, under the Parliament Act.

However, a backbench MP sponsoring the bill does not control parliamentary time and cannot table the procedural motions needed to carry the bill through its remaining stages. Without Government support – either by allocating time or tabling the necessary motions – the Commons’ expressed intention may ultimately be incapable of being realised.

The Government would arguably therefore have a constitutional responsibility to facilitate the House of Commons’ decision, by providing the time and procedural motions necessary to give effect to it. A failure to do so could be seen as frustrating, through inaction, the Commons’ exercise of its constitutional primacy through the mechanism provided by the Parliament Act.

Providing procedural support need not compromise Government neutrality on the substance of the assisted dying bill. It would be facilitating the statutory right of the elected House to determine whether to insist upon legislation it has previously approved, rather than endorsing the policy of assisted dying itself.

Option 1: Private Member’s Bill (PMB) Ballot. An MP successful in the PMB ballot could adopt the version of the assisted dying bill passed at Third Reading in the Commons in the first session. The ballot is expected to take place on 21 May 2026, with First Reading of the 20 ballot bills likely to be on 17 June 2026. To have a realistic prospect of progress, the sponsoring MP would need to rank in the top seven in the ballot, to secure a guaranteed Second Reading.

The ballot bill route to passing an identical bill has been attempted twice before without success: for the European Union (Referendum) Bill (in the 2013-14 and 2014-15 Sessions) and the Hunting Trophies (Import Prohibition) Bill (in the 2022-23 and 2023-24 Sessions).

Option 2: Presentation Bill. Any MP may introduce a Presentation Bill, which is another form of Private Members’ Bill. However, these rank behind ballot bills in the allocation of parliamentary time and rarely make progress without Government support.

Option 3: Government Bill with free votes. Procedurally, this would be the simplest and most time-efficient route. The Government could introduce the legislation while allowing MPs a free vote on all its provisions. There are precedents for this: the Hunting Act 2004; the Marriage (Same Sex Couples) Act 2013; and the War Crimes Act 1991. However, the Government has so far shown little indication that it is willing to adopt this approach.

Historically, bills proceeding under the Parliament Act have been subject to only minimal amendment. The bill passed in the second session in the House of Commons must correspond to the version passed by the Commons at Third Reading in the first session, subject to only two limited exceptions.

• Technical changes arising from the passage of time. Only minor consequential updates are permitted. In practice, this would likely extend no further than updating the year in the assisted dying bill’s short title.

• Incorporation of amendments agreed by the Lords in the first session. However, it is uncertain whether amendments made by the Lords in the first session but never communicated to the Commons because the bill did not complete its Lords stages, may be included in the second-session bill. The Lords agreed only three amendments in the first session. The question will ultimately fall to the Speaker to determine.

Although the “identical bill” requirement is restrictive, two additional mechanisms exist for altering the legislation in the second session.

• “Suggested amendments”. The Commons may attach suggested amendments when sending the bill to the Lords in the second session. These do not formally alter the text of the bill and therefore preserve its “identical” status. If the Lords then agree to some of those suggested amendments, while still rejecting the bill overall, those agreed suggested amendments may nevertheless be incorporated into the final enacted version. This mechanism has been used only rarely. Suggested amendments have been debated on just four occasions and formally proposed only twice, and no suggested amendment has ever been accepted by the Lords.

• Lords amendments in the second session. If the Lords amends the bill in the second session and the Commons agrees to those amendments, they may be included in the final text enacted under the Parliament Act.

Every previous use of the Parliament Act has involved departures from standard Commons procedures.

Because the bill agreed by the Commons in the second session must remain “identical” to that in the first, the Parliament Act did not envisage a conventional amendment process. In previous Parliament Act cases, Committee and Report stages have been dispensed with altogether or retained only in nominal form.

As decisions on whether to hold a suggested amendments stage – and which suggested amendments should be selected for debate – ordinarily fall to the Government in relation to Government bills, this may imply that, for a Private Member’s Bill, those decisions should instead rest with the backbench Member in charge of the bill, including whether a suggested amendments stage should occur and the form it should take.

However, there is no obligation for such a stage to take place, or for the House to consider every suggested amendment proposed. Where suggested amendments are tabled, a decision will need to be made as to which are selected for debate. Possible approaches include limiting debate to suggested amendments from the bill’s sponsor; permitting all tabled amendments to be debated; or adopting a more selective approach.

A decision will need to be made about how and when to implement the necessary procedures, and how much time to allocate to each stage. For a Government bill, these matters would be determined by Ministers. For a Private Member’s Bill, however, the position is less clear, as backbench MPs cannot ordinarily table motions governing procedures and the allocation of time in the Commons chamber. Key questions for the assisted dying bill would include:

• whether a procedural motion should be moved before or after Second Reading;

• whether, and if so when, a “suggested amendments” stage should be held;

• whether all Commons stages should be completed in a single sitting or over two or more days;

• when any money resolution should be introduced; and

• whether a substantive Third Reading debate should be held before the final vote.

The Member in charge of the bill could still attempt to steer it through the usual PMB process. However, doing so would be considerably more difficult. The bill would need to pass Second Reading on one of the 13 designated PMB Fridays; navigate Committee and Report Stage without amendment; and then be given a Third Reading. There would be no provision for a “suggested amendments” stage.

The process could be eased if one or more additional sitting Fridays were secured specifically for consideration of the assisted dying bill, outside the normal constraints of the 13 Friday sittings. This could be done by tabling an amendment to the Government’s motion proposing the dates for the session’s 13 sitting Fridays. This motion is normally tabled after the PMB ballot but before the presentation of the ballot bills. Whether an amendment of this kind – to add one or more dates to the list proposed by the Government – would fall within scope of the motion would ultimately be a matter for the Speaker to decide.

Alternatively, the Backbench Business Committee could also be asked to facilitate the passage of the bill by allocating time for a debate on one or more of the following:

• A motion calling on the Government to allocate parliamentary time and provide procedural support necessary for the bill’s passage.

• A procedure motion setting out how the bill should proceed – for example, specifying the time to be allocated for Second and Third Reading; dispensing with Committee and Report Stages; and providing for a time-limited debate on “suggested amendments” and determining who should select the motions for consideration. It would be for the Committee to determine whether a motion of this sort was within its remit.

• A motion to create one or more additional sitting Fridays beyond the 13 ordinarily allocated for Private Members’ Bills, to be dedicated to debate on the assisted dying bill.

Once sent to the Lords, the bill would proceed through the conventional legislative stages in the upper House. If the Commons attaches “suggested amendments” to the bill, the Parliament Act expressly requires the Lords to consider them. Three outcomes are then possible.

• The Lords pass the bill. This may occur either without amendment, allowing the bill to proceed directly to Royal Assent, or with amendments, resulting in ping-pong between the two Houses. If agreement is ultimately reached, the bill would become law through the ordinary legislative process without the need to invoke the Parliament Act.

• The Lords reject the bill outright. Rejection may occur through defeat at Second or Third Reading; failure to complete proceedings before the end of the session; or insistence on amendments unacceptable to the Commons. In those circumstances, the bill would receive Royal Assent under the Parliament Act.

• The Lords reject the bill overall but accept some “suggested amendments” proposed by the Commons. The bill could still proceed under the Parliament Act, with the agreed suggested amendments incorporated into the final enacted text.

The timing of Royal Assent under the Parliament Act depends on when the House of Lords is treated as having rejected the bill.

• If the Lords reject the bill at Second or Third Reading, Royal Assent may follow immediately thereafter.

• If the bill progresses further but fails to complete its passage, rejection is treated as occurring at the end of the session.

Even where all the statutory conditions have been satisfied, the House of Commons could still decide not to invoke the Parliament Act. In the absence of such a decision, the bill would proceed automatically to Royal Assent once certified by the Speaker.

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