Explained: What Is A Three-Line Whip?

11 September 2017, 18:45 | Updated: 11 September 2017, 18:53

Jeremy Corbyn has issued a three-line whip to his party demanding that MPs vote against the government’s EU Withdrawal Bill - but what does that mean?

It’s a term that crops up regularly in politics and the Labour leader is facing a blow to his authority as a number of Labour MPs look set to defy him on the central piece of Brexit legislation.

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.