Explained: What Is A Three-Line Whip?

11 September 2017, 18:45 | Updated: 28 October 2019, 15:53

Some of Theresa May's cabinet members abstained on a three-line whip tonight in a crunch vote over a no-deal Brexit - but what does that mean?

It’s a term that crops up regularly in politics and the PM's suffered another blow to her authority after some of her own government ignored orders.

What is a three-line whip?

Put simply, a three-line whip is an instruction given to MPs by the leader of their party to vote a certain way on a specific issue.

Each Thursday all members of Parliament are given a whip for the following week and are told which debates are happening and which legislation is going through the Commons.

Under each piece of legislation is either one, two or three lines - representing a one-line whip, two-line whip or three-line whip.

A single line is guidance, a double line requires attendance and is expected to be adhered to.

However, a three-line whip is serious and any MP who doesn’t adhere to it risks their position being questioned.

As Iain Dale explains: “If you go against your party on a three-line whip and you vote against them it means you’re a persona non grata - you will not get promoted for at least the next two years.”

Watch above for a full, simple explanation of whips.