What is the alternative vote?
So the Liberal Democrats have been promised a referendum on the alternative vote (AV) as part of the deal to support the Conservatives in a coalition government. But what is AV?
AV retains single member constituencies but voters number candidates in order of preference.
If the top candidate fails to receive 50% of the vote, the lowest candidate is eliminated and his/her second preferences are allocated to the remaining candidates.
If necessary, the process continues until the top candidates has 50% of the votes.
It is not a proportional system, but it ensures that every Member of Parliament has been supported by a majority of those voting in his/her constituency even if he/she was not the voter’s first choice.
It would help the Liberal Democrats – but not by much.