Review AP Comparative Government Unit 2 to understand how executive, legislative, and judicial institutions are structured across China, Iran, Mexico, Nigeria, Russia, and the United Kingdom. This unit carries up to a third of the exam and tests your ability to compare how institutional design shapes power, stability, and policymaking.
Use the topic guides, key terms, and practice questions available for every topic in this unit to build your comparison skills before exam day.
Unit 2 is the institutional backbone of AP Comparative Government. Every comparison question on the exam ultimately traces back to how a country's branches of government are designed, who holds real power, and what checks exist on that power. Understanding these structures in all six countries is essential for both multiple-choice and free-response tasks.
The UK uses a parliamentary system with fusion of powers; Mexico and Nigeria use presidential systems with separation of powers; Russia uses a semi-presidential system. Each design shapes how executives are chosen, how accountable they are, and how easily policy gets made.
China and Iran have unicameral legislatures that are heavily constrained by the CCP's Politburo Standing Committee and Iran's Guardian Council respectively. Mexico, Nigeria, Russia, and the UK all use bicameral legislatures with varying degrees of real independence.
Judicial independence ranges widely: Mexico and Nigeria are moving toward stronger review powers, the UK operates under parliamentary sovereignty, and China, Russia, and Iran all subordinate courts to party or religious authority. The distinction between rule of law and rule by law is central to this unit.
The core argument of Unit 2 is that institutional design is not neutral. Whether a country fuses or separates powers, whether its legislature can act independently, and whether its courts can overrule the executive all determine how stable, legitimate, and accountable a government is. Comparing these structures across the six countries is the primary skill the AP exam tests in this unit.
Defines the three system types using UK (parliamentary), Mexico and Nigeria (presidential), and Russia (semi-presidential) as examples. Focuses on how the executive gains power and whether it depends on legislative confidence.
Compares institutional relations across system types, focusing on policy obstacles, parliamentary checks like censure and Question Time, and the difference between fused and separated branch powers.
Describes executive structure in all six countries: China's party-state-military fusion, Iran's dual executive under the Supreme Leader, Mexico's sexenio presidency, Nigeria's presidential system, Russia's dominant presidency, and the UK's prime minister.
Analyzes the advantages and disadvantages of term limits for stability and effective policymaking, with examples including Mexico's single sexenio and the tradeoffs of lame-duck periods versus checks on personality rule.
Describes how legislatures can remove executives through impeachment in presidential systems and votes of no confidence in parliamentary systems, and explains why removal is practically difficult in authoritarian contexts.
Covers the structure and powers of each country's legislature: unicameral systems in China and Iran, and bicameral systems in Mexico, Nigeria, Russia, and the UK, with specific powers of each chamber.
Explains how outside institutions constrain legislative independence, focusing on China's Politburo Standing Committee and NPC Standing Committee, and Iran's Guardian Council and Expediency Council. Also covers how legislatures build legitimacy.
Describes judicial structure and appointment methods in all six countries, distinguishing between rule of law and rule by law systems and identifying how each country's courts interpret and apply law.
Explains what makes a judiciary independent: authority to overrule other branches, appointment and removal processes, term length, and professional requirements. Connects judicial independence to checks and balances and protection of rights.
This snapshot uses Fiveable practice activity to show where students tend to miss questions and which review moves are worth prioritizing first.
Across 17k multiple-choice practice attempts for this unit.
Practice activity included in this snapshot.
Across 104 scored free-response attempts for this unit.
Review Legislative Systems with attention to how the concept appears in AP-style source and evidence questions.
Review Judicial Systems with attention to how the concept appears in AP-style source and evidence questions.
Review Independent Judiciaries with attention to how the concept appears in AP-style source and evidence questions.
Review Parliamentary, Presidential, and Semi-Presidential Systems with attention to how the concept appears in AP-style source and evidence questions.
These three system types define how the executive and legislature relate to each other. In parliamentary systems the executive is drawn from the legislature and depends on its confidence. In presidential systems the executive is separately elected and serves a fixed term. Semi-presidential systems split executive power between a directly elected president and a prime minister who must maintain legislative support.
| Feature | Parliamentary (UK) | Presidential (Mexico/Nigeria) | Semi-Presidential (Russia) |
|---|---|---|---|
| Executive selection | Chosen by legislature | Directly elected | President directly elected; PM nominated by president |
| Executive removal | Vote of no confidence | Impeachment only | Both mechanisms possible |
| Head of state vs. government | Separate (monarch/PM) | Same person (president) | President is head of state; PM heads government |
| Cabinet accountability | To legislature | To president | To both president and legislature |
| Branch relationship | Fused | Separated | Hybrid |
Parliamentary systems face fewer formal obstacles to passing policy because the executive controls the legislative majority. However, parliaments retain real checks: they can censure ministers, reject executive legislation, hold question time, and set deadlines for calling elections. Presidential systems create more institutional friction through divided branch powers but make executive removal much harder.
| Check on Executive | Parliamentary System | Presidential System |
|---|---|---|
| Removal mechanism | Vote of no confidence | Impeachment |
| Legislative rejection of policy | Yes, can defeat government bills | Yes, through veto and override |
| Questioning executive | Question Time (PMQs in UK) | Committee hearings |
| Censure of ministers | Yes, formal censure motions | Limited; impeachment is primary tool |
Each course country has a distinct executive structure. China's president combines party, state, and military leadership. Iran's Supreme Leader holds supreme authority above the elected president. Mexico's president serves a single sexenio. Nigeria's president serves up to two four-year terms. Russia's president dominates the semi-presidential system. The UK's prime minister leads the parliamentary majority. Term limits shape how long executives can hold power and carry real tradeoffs for stability and accountability.
Legislative branches across the six countries can remove executives, but the procedures and practical likelihood differ sharply by system type. Presidential systems use impeachment; parliamentary systems use votes of no confidence. In authoritarian or hybrid systems, formal removal mechanisms exist on paper but are rarely used against the dominant leader.
Legislative structure varies from unicameral to bicameral and from genuinely independent to heavily constrained. China and Iran have unicameral legislatures that are formally powerful but practically subordinate to party or theocratic institutions. Mexico, Nigeria, Russia, and the UK all use bicameral systems. Legislative independence depends on whether outside bodies can override, veto, or control the legislature's agenda and membership.
| Country | Structure | Key Constraint on Legislature |
|---|---|---|
| China | Unicameral (NPC) | Politburo Standing Committee; NPC Standing Committee controls agenda |
| Iran | Unicameral (Majles) | Guardian Council vets candidates and reviews legislation |
| Mexico | Bicameral | Presidential veto; relatively independent |
| Nigeria | Bicameral | Presidential veto; relatively independent |
| UK | Bicameral (Commons/Lords) | Parliamentary sovereignty; Lords has limited delaying power only |
Judiciaries differ in how judges are appointed, how long they serve, and whether courts can actually overrule the executive or legislature. The key conceptual divide is between rule of law (law constrains the government) and rule by law (government uses law as a tool). Judicial independence depends on appointment processes, term length, removal procedures, and the professional standards required of judges.
| Country | Rule of Law or Rule by Law | Key Independence Factor |
|---|---|---|
| China | Rule by law | CCP controls appointments; no independent review |
| Iran | Rule by law (religious) | Supreme Leader appoints judiciary head; Sharia compliance required |
| Mexico | Transitioning toward rule of law | Judicial review exists; 15-year terms; Senate confirmation |
| Nigeria | Transitioning toward rule of law | Judicial council recommends appointments; presidential nomination |
| UK | Rule of law | Parliamentary sovereignty limits judicial review of primary legislation |
Try AP-style multiple-choice questions and written prompts after you review the notes.
| Term | Definition |
|---|---|
| Parliamentary Systems | Government systems in which the executive is drawn from and accountable to the legislature; the prime minister leads the majority party or coalition and can be removed by a vote of no confidence. Example: United Kingdom. |
| Presidential Systems | Government systems with a separately elected president who serves a fixed term as both head of state and head of government; the cabinet is accountable to the president, not the legislature. Examples: Mexico, Nigeria. |
| Semi-Presidential System | A hybrid system with a directly elected president as head of state and a prime minister who must maintain legislative support; the cabinet is accountable to both. Example: Russia. |
| fusion of powers | A feature of parliamentary systems in which the executive is integrated with the legislature, allowing the executive to exercise legislative authority and vice versa. |
| sexenio | Mexico's single non-renewable six-year presidential term, which prevents re-election and limits incumbency advantage but creates a lame-duck dynamic late in the term. |
| Lame Duck Period | The phase near the end of a fixed executive term when the officeholder has reduced political leverage because they cannot seek re-election or are soon leaving office. |
| Impeachment | A formal legislative process charging a president or other executive official with wrongdoing; used in presidential systems like Mexico and Nigeria as the primary removal mechanism. |
| Guardian Council | Iran's 12-member body that vets candidates for the Majles and reviews all legislation for compatibility with Islamic law, effectively constraining legislative independence. |
| Expediency Council | An Iranian body appointed by the Supreme Leader that resolves disputes between the Majles and the Guardian Council and advises the Supreme Leader on policy. |
| National People's Congress | China's unicameral legislature, constitutionally the most powerful institution, but in practice subordinate to the CCP's Politburo Standing Committee; elects the president and approves the premier. |
| Politburo Standing Committee | The seven-member body at the top of the Chinese Communist Party that makes real governing decisions, effectively controlling the NPC's agenda and China's policy direction. |
| Rule of Law | The principle that all individuals and institutions, including the government, are subject to and accountable to law that is fairly applied. Contrasts with rule by law, where the government uses law as a tool of control. |
| Judicial Independence | The degree to which courts can rule against the executive and legislature without political interference, determined by appointment processes, term length, removal procedures, and the authority to overrule other branches. |
| Majles | Iran's unicameral elected parliament that approves legislation, oversees the budget, and confirms cabinet nominees, but operates under Guardian Council supervision for Sharia compliance. |
| Supreme Leader | Iran's highest authority, who sets the political agenda, commands the military, appoints key officials including the judiciary head and half of the Guardian Council, and operates above the elected president. |
In presidential systems like Mexico and Nigeria, one person holds both roles. In parliamentary systems like the UK, the monarch is head of state and the prime minister is head of government. In Iran, the Supreme Leader and the president split these functions in a unique way that does not fit neatly into either category.
The constitution designates the NPC as the most powerful institution, but in practice the Politburo Standing Committee makes real decisions. The NPC largely ratifies those decisions. Do not describe the NPC as independently powerful.
Parliamentary systems have fewer formal veto points than presidential ones, but they still have real checks: censure motions, Question Time, refusal to pass legislation, and the vote of no confidence. Do not say parliamentary executives are unchecked.
The Guardian Council vets candidates and reviews legislation for Sharia compliance. The Expediency Council resolves disputes between the Majles and the Guardian Council. They are separate institutions with different functions, both appointed or overseen by the Supreme Leader.
All six countries have courts, but not all operate under rule of law. China and Russia use courts as instruments of state power (rule by law). Having a judiciary does not mean that judiciary is independent or that the government is constrained by law.
The AP exam frequently asks you to compare how a specific institutional feature, such as executive removal, legislative structure, or judicial appointment, works differently in two or more course countries. Practice identifying the relevant institution, naming its structural feature, and explaining the consequence for power or accountability. Avoid vague answers; name the specific body (e.g., Guardian Council, Politburo Standing Committee) and its function.
Free-response tasks in AP Comparative Government often ask you to explain why an institutional arrangement produces a particular outcome, such as why term limits can both check power and reduce accountability, or why parliamentary systems face fewer policy obstacles than presidential ones. Practice building explanations that move from institutional design to political consequence using specific country evidence.
The exam tests whether you can use institutional evidence to support claims about regime type. For example, CCP control of judicial appointments and the NPC's rubber-stamp role are evidence of authoritarian consolidation in China, while Mexico's judicial review power and Senate confirmation process are evidence of democratic institution-building. Practice connecting Unit 2 institutional details to the regime classification concepts from Unit 1.
Open the individual guides for Unit 2 when you want a closer review of one topic.
browse guidesPractice free-response reasoning and compare your answer with scoring guidance.
practice FRQsWatch past review streams filtered to Unit 2 when you want a video walkthrough.
open videosUse unit cheatsheets for a quick visual review after you work through the notes.
open cheatsheetsEstimate your broader AP score goal after you review the course and exam format.
open calculatorAP Comp Gov Unit 2 covers 9 topics focused on how governments are structured and how power is exercised. Topics include Parliamentary, Presidential, and Semi-Presidential Systems (2.1-2.2), Executive Systems and Term Limits (2.3-2.4), Removal of Executives (2.5), Legislative Systems and Independent Legislatures (2.6-2.7), and Judicial Systems and Independent Judiciaries (2.8-2.9). The big thread running through all 9 topics is how institutional design shapes stability, legitimacy, and policy. You'll compare how the UK, Mexico, Russia, China, Iran, and Nigeria each structure their branches of government. See the full topic list at /ap-comp-gov/unit-2.
Unit 2 makes up 22-33% of the AP Comp Gov exam, making it one of the most heavily tested units on the entire test. It covers political institutions, including executive, legislative, and judicial systems across the six course countries. Because the exam weight is so high, questions about parliamentary vs. presidential systems, executive term limits, and judicial independence show up constantly, both in multiple-choice and free-response sections. Knowing how each country's institutions work, and how to compare them, is essential for a strong score.
The AP Comp Gov Unit 2 progress check includes both MCQ and FRQ parts drawn from all 9 topics in the Political Institutions unit. The MCQ section tests your ability to identify and compare parliamentary, presidential, and semi-presidential systems, explain executive term limits and removal processes, and distinguish independent from dependent legislatures and judiciaries. The FRQ part of the progress check typically asks you to compare institutional structures across two or more course countries, such as explaining how the UK's parliamentary system differs from Mexico's presidential system, or analyzing what makes a judiciary independent. To prep for the progress check, review each topic's key concepts and practice applying them to specific countries at /ap-comp-gov/unit-2.
AP Comp Gov Unit 2 FRQs most often ask you to compare executive, legislative, or judicial systems across two or more of the six course countries, explain how a specific institutional feature affects stability or legitimacy, or analyze the consequences of executive removal or term limits. The most common question types are Comparative Analysis and Conceptual Analysis prompts. To practice effectively, pick one topic at a time, such as Independent Judiciaries (2.9) or Executive Term Limits (2.4), and write a short response comparing two countries. Focus on using specific evidence, like China's National People's Congress vs. the UK's Parliament, rather than general claims. You can find practice prompts and study guides at /ap-comp-gov/unit-2.
You can find AP Comp Gov Unit 2 multiple-choice questions, practice tests, and FRQ prompts covering Political Institutions at /ap-comp-gov/unit-2. That page organizes practice by topic, so you can target specific areas like Legislative Systems (2.6) or Judicial Independence (2.9) before moving to full unit practice tests. For MCQ practice, focus on questions that ask you to identify system types, compare institutional features across countries, and interpret scenarios involving executive removal or legislative power. Mixing topic-level MCQs with timed full-unit practice tests is the most efficient way to build confidence before exam day.
Start by building a comparison chart for the three system types covered in topics 2.1 and 2.2: parliamentary, presidential, and semi-presidential. Map each of the six course countries to its system type, then add columns for executive powers, term limits, removal processes, legislative structure, and judicial independence as you work through topics 2.3-2.9. Here's a concrete study plan that works well for this unit: - **Week 1:** Study topics 2.1-2.5 (executive systems). For each country, note who holds executive power and how they can be removed. - **Week 2:** Study topics 2.6-2.9 (legislative and judicial systems). Focus on what makes a legislature or judiciary truly independent. - **Week 3:** Practice FRQs comparing two countries on one institutional feature, then review your chart before the progress check. Since Unit 2 is worth 22-33% of the exam, time spent here pays off more than almost anywhere else. Find topic guides and practice at /ap-comp-gov/unit-2.