AP® Comparative Government and Politics review sheet from Aim for Five (aimforfive.com/comp-gov/units/2/2-2)
Unit 2 · Topic 2.2
2.2 Comparing Parliamentary, Presidential, and Semi-Presidential Systems
Each executive system has trade-offs. Parliamentary systems usually let a government pass its program quickly and keep it answerable to the legislature, but can concentrate power. Presidential systems add checks and fixed terms but can produce gridlock. Semi-presidential systems try to mix the two.
Key terms
- separation of powers
- fusion of powers
- gridlock
- vote of no confidence
- checks and balances
Parliamentary systems: strengths and weaknesses
Because the prime minister leads the majority, the government can usually pass its laws without a long fight. The UK government controls most of the Commons timetable, and strict party discipline means MPs usually vote with their party. Accountability is direct: ministers face questions in Parliament, and the Commons can bring down the government with a vote of no confidence.
Parliament has other checks as well. It can censure ministers, vote down the government's bills and question ministers in public, and the law sets a deadline for the next election: in the UK, at least every five years.
The flip side is that a government with a large majority faces few checks between elections. A former UK minister called this an “elective dictatorship.” Backbench rebellions, the House of Lords, the courts and devolved governments are the main brakes.
Presidential systems: strengths and weaknesses
Separation of powers means the president and legislature check each other. The president has a fixed term, which brings stability, and a personal mandate from voters.
But if the legislature is controlled by other parties (divided government), the branches can deadlock. Between 1997 and 2018, Mexican presidents' parties lacked a majority of their own in the Chamber of Deputies, so presidents had to bargain with other parties to pass major reforms. Fixed terms also make it hard to remove a president who loses public support. Nigeria's presidents have at times clashed with the National Assembly over budgets and appointments.
Semi-presidential systems
These systems give an elected president a strong role while keeping a prime minister answerable to the legislature. If the president and the legislative majority come from different parties, they may have to share power. In Russia the president has dominated, appointing prime ministers who carry out the president's agenda, and the pro-presidential United Russia party has controlled the Duma.
France, which is not a course country, is the model for this system. When the French president's party loses control of the legislature, the president must appoint a prime minister from the other side, an arrangement called cohabitation.
Side-by-side comparison
| Feature | Parliamentary (UK) | Presidential (Mexico, Nigeria) | Semi-presidential (Russia) |
|---|---|---|---|
| Executive chosen by | Legislature's majority | Voters directly | President elected by voters; PM appointed with Duma approval |
| Removal | Vote of no confidence or party change of leader | Impeachment only | President by impeachment; government by no confidence |
| Speed of lawmaking | Usually fast | Can be slow if branches disagree | Fast when the president controls the Duma |
| Main risk | Executive dominance | Gridlock | Concentration of power in the president |
Worked examples
Try each one yourself first, then open the solution.
- Example 1
Explaining a trade-off
Explain one advantage and one disadvantage of a parliamentary system compared with a presidential system.
Show the solutionHide the solution
- Step 1: Advantage: fusion of powers means the government usually controls a majority, so it can pass its program efficiently. Example: UK governments with large Commons majorities pass most of their bills.
- Step 2: Disadvantage: the same fusion weakens checks between elections, because the legislature's majority supports the executive.
- Step 3: Make each point comparative by saying how a presidential system differs: separate elections produce stronger checks but risk gridlock.
Answer: Advantage: easier passage of laws because the executive leads the legislative majority. Disadvantage: fewer checks on a government with a large majority, unlike the separate branches of a presidential system.
Common mistakes
- Saying parliamentary systems have no checks. Question time, committees, confidence votes, the Lords and party rebellions all check the UK government.
- Claiming presidential systems always produce gridlock. It happens mainly under divided government.
- Forgetting that a parliamentary government can fall between elections, while a president normally serves a fixed term.
On the exam
- Questions often ask why a country might choose one system over another. Tie your answer to efficiency, accountability, stability or checks on power.
- Comparative analysis prompts may pair the UK with Mexico or Nigeria. Use specific institutions on both sides.
Connected topics
Videos
Check yourself
5 questions on 2.2 Comparing Parliamentary, Presidential, and Semi-Presidential Systems. Pick an answer to see if you got it, and why.
From 1997 until 2018, no Mexican president's party held a majority of seats in the Chamber of Deputies on its own. This situation most likely made it harder for presidents to
Which of the following is a way the UK House of Commons checks the executive?
Which statement best compares parliamentary and presidential systems?
In Country L, the prime minister leads the party with the most seats in the lower house of the legislature, and every cabinet minister is also a member of that house. After a scandal, a group of members from the governing party announces it will no longer support the government.
Opposition leaders immediately introduce a motion stating that the house has no confidence in the government. The prime minister responds that, if the motion passes, the country will hold a new election.
Hypothetical scenario
If the motion described in the scenario passes, the most likely result is that
Compared with a presidential system such as Nigeria's, the system in Country L is most likely to
0 of 5 answered