Jo Swinson, the Liberal Democrat Shadow Scottish Secretary, tabled a bill on 17 May at Westminster to amend the Scotland Act and allow the use of the Single Transferable Vote system for the 2011 Scottish Parliamentary elections. At the same time, the Scottish Liberal Democrat leader Nicol Stephen lodged a motion in the Scottish Parliament calling for the UK government to introduce such legislation. The Liberal Democrats believe that STV represents the fairest system of election and that having one system of election will improve public confidence.

Dr Ken Ritchie, Chief Executive of the Electoral Reform Society, said that "The events of 3 May revealed major inadequacies in the processes electing Members of the Scottish Parliament. But the same day, local government elections held under STV have managed to deliver decent local government to Scotland." The Society's own figures show that the spoilage rate for the council elections under the new STV system was 1.98% compared to 3.5% for the Parliamentary elections, which used the Additional Members Scheme with its mix of First Past the Post and a proportional list system. The Society says that this demonstrates that the Scots can use the STV system and that its use should now be expanded to other elections.