Do you think it looks bad for Theresa May next week?  If so, know now that it’s even worse than you thought.

On Tuesday, the Commons will hold a “meaningful vote” on the Government’s Brexit plan. It it is defeated, the Prime Minister has pledged to hold a vote on No Deal the following day.  If the House votes against that too, she has promised a vote on extension on Thursday.

Now it is possible that those last two votes may not happen at all.  If she loses on Tuesday, May could seek to avoid those later votes – which would split her Party, enrage the parts of her Party on the losing side in each, and threaten her own position.  She might argue that instead of holding them, her deal should be put to the Commons for the third time.  We shall see.

But either way, an important procedural aspect of Tuesday’s vote, and potentially of those later votes too, is being underplayed.  The Government motion in each case is amendable.

This means that Labour, the ERG, Oliver Letwin et al can seek to tack on to any motion that is debated any amendment that they want.  Each could try variously, for example, to force formal membership post-Brexit of the Customs Union.  Or to slap conditions on No Deal.  Or to specify a length for extension with which the Government disagrees.

Now MPs obviously can’t simply put down any amendment they like to anything they like.  Ultimately, the Speaker determines what’s in order, which amendments are selected, and which are voted on.  That’s more good news for the Government (not).

Furthermore, one procedural expert reminds this site that the MPs in question will have limited time in which to table amendments.  For example, if the Government’s Tuesday motion goes down, and it then tables a No Deal motion for Wednesday, MPs will only be able to table amendments to that motion while the House still sits. (Unless the Speaker takes manuscript amendments the next day.)

That would mean a race against the clock during the expected half hour of the adjournment debate which would follow the divisions on the meaningful vote.

But for all these tabling issues, Government and Commons alike face a nightmare – namely, if clashing amendments pass.

That this could happen isn’t some product of this site’s imagination.  For the House has passed such amendments only recently.  As recently as late January, it voted for both the Brady amendment, which sought to remove the backstop from the Withdrawal Agreement, and also for the Spelman amendment, which opposed No Deal.

It can be argued that, on paper, these ideals are not ultimately incompatible.  But the tensions between them caused plenty of problems for the Government in practice.  Last month, the ERG refused to support a Government motion apparently supporting both Brady and Spelman.  Nearly a quarter of Tory MPs failed to back May in the lobbies.

So it is not absurd to imagine the Commons, this week, voting both for the Customs Union and against it; against No Deal, but with conditions that might still allow it; for or extensions of different lengths.  These are “known unknowns”.  All are admittedly unlikely.  However, there will also be unknown unknowns which by definition are unseen.

This not so much a can of worms as a can of serpents. Welcome to the Government’s latest hell.