According to Quentin Letts in the Daily Mail (which is not usually a friend of electoral reform) on 1 May 2014, Sir Robert Rogers, Clerk of the Commons, wrote a letter to the Speaker announcing his departure. “The letter spoke of how Parliament is today better at scrutinising the Executive than it used to be. Indeed it is. That is partly because it is a hung [i.e. balanced] Parliament…….”
One of the objections often voiced against STV and other proportional voting systems is that they encourage so-called hung parliaments, which are portrayed as bad and undesirable.
In fact, balanced parliaments, as we prefer to call them, can occur with any voting system (except the North Korean and similar!) and the UK has one now with First Past The Post. However, with a proportional system and especially with STV, Parliament is representative of voters so there is a balanced parliament when voters are balanced.
Far from being bad and undesirable, balanced parliaments are good and desirable because, as Sir Robert has remarked, they enhance Parliament’s ability to scrutinize the Executive, which is meant to be one of its key functions.
So, far from being an argument against STV, the possibility of a balanced parliament is an argument for STV; it makes governments more accountable.