Why can't Labour remove its former candidate from Rochdale ballot papers?

Electoral law means ballot papers effectively cannot be changed after publication.

Ballot papers are "a snapshot in time", explains Peter Stanyon, the chief executive of the Association of Electoral Administrators,

The only exception to this is, he says, is in the event of a candidate's death.

Mr Stanyon explains nominations must be closed 19 working days before the date of any election "regardless of there being any change in circumstances", and Mr Ali was confirmed as the Labour candidate on Friday 2 February.

That means the party's withdrawal of support on Monday 12 February is too late to change the ballot paper before the by-election, which will take place on 29 February.

He says: "The ballot paper will be as it would have been had there not been the situation that's developed, so he will be on the ballot paper in alphabetical order with the description of the Labour Party candidate standing on behalf of the party.

"Even if the candidate decides they don't want to stand with the party ticket, it's a snapshot in time at the point they made their nominations, so you can't withdraw your party description or your candidate after the deadline."

The party has no control over what their former candidate does if elected, Mr Stanyon says, as "ultimately the person being elected is the person not the party".

He adds: "It would very much rest with Mr Ali - if he was elected and chose then to resign we're back into the same process again of another by-election with a new timescale running from whenever the day of that election is called."

Voters in Rochdale will also see Guy Otten listed as the Green Party candidate, despite having quit the race earlier this month.

The main reason for the deadline being 19 working days before voting is because of postal voting, Mr Stanyon explains, with time needed for postal votes to go out internationally.

The date of the poll is decided by MPs and the returning officer works backwards from that date, often scrambling to organise ballot papers, polling stations and staff on a short timescale.

This is not the first time candidates who have had party support withdrawn have appeared as official candidates on polling day.

Neale Hanvey was listed as the SNP candidate in the 2019 general election, despite having been suspended from the party for using antisemitic language. He was elected as the MP for Kirkcaldy and Cowdenbeath, and readmitted to the SNP some months later.