<P> A recent World Bank study found that parliamentary systems are associated with less corruption. . This study's findings are supported by a separate study that arrived at the same conclusions. . </P> <P> Some constituencies may have a popular local candidate under an unpopular leader (or the reverse), forcing a difficult choice on the electorate . Mixed - member proportional representation (where voters cast two votes) can make this choice easier by allowing voters to cast one vote for the local candidate at the constituency level but also cast a second vote for another party at the wider parliamentary level . </P> <P> Although Bagehot praised parliamentary government for allowing an election to take place at any time, the lack of a definite election calendar can be abused . Previously under some systems, such as the British, a ruling party could schedule elections when it felt that it was likely to retain power, and so avoid elections at times of unpopularity . (Election timing in the UK, however, is now partly fixed under the Fixed - term Parliaments Act 2011 .) Thus, by wise timing of elections, in a parliamentary system a party can extend its rule for longer than is feasible in a functioning presidential system . This problem can be alleviated somewhat by setting fixed dates for parliamentary elections, as is the case in several of Australia's state parliaments . In other systems, such as the Dutch and the Belgian, the ruling party or coalition has some flexibility in determining the election date . Conversely, flexibility in the timing of parliamentary elections can avoid periods of legislative gridlock that can occur in a fixed period presidential system . Such feature in being able to time elections whenever it is advantageous to the ruling party is not a real issue, however, as voters ultimately have the ability to still make the choice of whether to vote for the ruling party or not . </P> <P> It has been well - observed that the rankings of top - performing countries according to performance indices such as List of countries by GDP (nominal) per capita, Human Development Index, Global Competitiveness Report, Corruption Perceptions Index, and many more performance indexes feature most of the best - performing countries having parliamentary systems, while most of the worst - performing countries have presidential systems or strong - president semi-presidential systems . This also extends to the fact that majority - if not all - of the countries that dominate top ranks of lists like the Global Liveability Ranking, the Mercer Quality of Living Survey, the Henley & Partners Passport Index, and many such ranking lists use parliamentary systems . In contrast, the List of cities by murder rate shows an overwhelming number of cities found in countries that use presidential systems . </P>

Who elects the leader in a parliamentary democracy