I was looking at the CIA World Factbook and I came across the government type of a parliamentary republic. This is obviously not the same thing as a constitutional republic. I was wondering about the differences between the two forms of government. Specifically, I was wondering if parliamentary republics have constitutions and if constitutional republics can have a parliament.
- In a parliamentary system, the people elect a legislature and the legislature elects a government.
- In a presidential system, the people elect a government and a legislature.
Both may or may not have a written constitution. The United Kingdom is widely accepted as a democracy, yet they have no written constitution and people cling to the fiction that the Crown-in-Parliament is anything other than the parliament telling the Queen what to do.
The term constitutional republic is used for both parliamentary and presidential republics when the civil rights, separation of powers, rule of law, etc. are laid down in a constitution.
A single counterexample is enough to prove a negative.
(Some people cling to the fiction that the German constitution be not a constitution because it is not called ‘constitution’ but Basic Law (Grundgesetz), but if you apply the duck test, it is a constitution.)
"Constitutional Republic" and "Parliamentary Republic" aren't mutually exclusive. A state can be both or neither.
Any republic where the system of government is described by a written constitution is a constitutional republic.
When the constitution says that the executive branch is legitimized by an elected parliament, then it is both a constitutional republic and a parliamentary republic.
When the constitution says that the head of the executive branch is legitimized by a separate election (like in the United States), then the country is both a constitutional republic and a presidential republic.
There are also a few states which do not have an official constitution. But if the state follows the principles of a democratic republic, then it is a democratic republic without being a constitutional republic. Like Isreal, for example.
There are also states with constitutions which are not republics at all. For example, North-Korea, an absolute dictatorship, has a constitution.