Legislatures have a significant role to play in the establishment and the continuation of stable democracies. A stable democracy is one, in which there is a balance of power between the executive, the legislature, and the judiciary.
A strong legislature plays an integral role within any stable democracy. Such a legislature needs to work closely with the executive branch, and the judiciary or civil service without completely controlling either of them. Legislatures have to be able to pass acts and laws, which allow for the country to be governed effectively without allowing democratic values to be weakened or by passed. Generally legislatures need to have a majority of members in favour of passing individual acts as well as having enough members backing the government for it's entire term in office. The strength of legislatures varies from state to state besides altering as a consequence of election results. Some countries have even altered the strength of their legislatures to reflect past experiences, for instance the legislature of the Fifth Republic in France was made weaker than in the Fourth Republic so that the President could have greater control over policies. In West Germany electoral systems and regulations were changed to prevent extreme parties gaining power as the Nazis did during 1933. Arguably such changes have been successful as France and Germany have stronger and more stable democracies than was the case after the First World War.
Conversely countries with quite similar constitions can have differing amounts of stability, for instance India and Pakistan.
Legislatures tend to have their respective powers set out in written constitutions, with the exception of the British Parliament that evolved over centuries. Whenever constitutions have put legislatures into place other aspects like electoral systems, voting ages and other rules are also put into place. When added together the objective is to obtain and maintain stable democracies. In theory well thought out constitutions and legislatures should always lead to stable democracies. Of course when the UK legislature began in the 13th century there was no thought about democracy, simply assisting the English monarchy in ruling the country by passing laws and raising increased levels of taxation. Similarly when the US Congress was set up it was with a limited franchise instead of universal suffrage, stability was considered more important than democracy itself. Legislatures then were designed to allow people who were wealthy enough to pay taxes to have representation when laws and taxes were introduced or changed. Concepts about democracy and universal (originally just male) suffrage owed more to the French Revolution than to either the Westminster Parliament or the US Congress.
The broadening of democracy in the UK and the US was a process, which was drawn out as opposed to been an over night event. In Britain it meant government controlled religious changes, the fighting of civil wars, and the role of the monarch getting reduced to that of a constitutional figurehead. Since the 18th century the head of government has been known as the Prime Minister, governing through powers derived from both Parliament and the royal prerogative. Parliament in general, and the House of Commons in particular claimed to have sovereignty over the entire UK. Full sovereignty was lost once Britain joined the EU yet in theory should be restored as soon as the Brexit process has ended (Silk & Walters, 1998 p. 15). In contrast the American system can grind to a halt whenever the White House is unable to reach agreement with Congress. It can hamper policy decision making in times of crisis such as the economic crisis of 2008.
The emergence of party systems has had a great impact on how legislatures have worked in the UK and US, also having an influence over how stable democracy has been in both countries. Political parties in both cases evolved as opposed to already existing when the legislatures were founded. The UK and US tend to have just two main political parties at first glance. This means that the majority of voters belief that in elections they can vote for A, or that they can vote for B. There are third parties in the UK yet none have replaced the Conservatives or Labour since the Labour party itself replaced the Liberals after 1918.
Therefore having a strong legislature is an important factor in any stable democracy. It is one of several factors, which contribute to stable democracies such as electoral systems, liberal culture, differences in constitutions, and changes in political parties. The strength of legislatures can alter with election results, arguably been weaker during periods of coalition or minority government. In the US the power of Congress will be more or less influential depending on if it is controlled by the same party as the President belongs to. In the American case a strong Congress does not lead to effective administration even it is elected. The checks and balances often leading to gridlock as well as inertia, particularly in relation to the federal budget. In Britain when a government lacks a majority then the government is considered to be weak yet conversely the MPs seem to have more power over what happens in the House of Commons.
Eatwell R & Wright A (2003) Contemporary Political Ideologies 2nd edition, Continuum, London
Silk P & Walters R (1998) How Parliament Works 4th edition, Longman, London & New York
Stone O & Kuznick P (2013) The Untold History of the United States, Ebury Press, London
Democracy over the centuries has had it's share of both admirers and critics yet a large majority of contemporary governments claim to be democratic in some aspect or another..