How do the UK and US constitutions, legislatures, executives and courts compare?
Component 3A.6.2 to 6.8: comparing and debating the UK and US constitutions, legislatures, executives and judiciaries, and how rational, cultural and structural approaches account for the similarities and differences.
An Edexcel A-Level Politics Component 3 answer comparing UK and US government, covering the codified and uncodified constitutions, the legislatures, the powers of the president and prime minister, the relative independence of the two supreme courts, and how rational, cultural and structural approaches explain the similarities and differences.
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What this dot point is asking
Edexcel wants you to compare and debate the UK and US constitutions, legislatures, executives and judiciaries, and to explain how the rational, cultural and structural approaches account for the similarities and differences. This is examined through the 30-mark Section C synoptic essays, which require comparison plus a comparative approach.
Comparing the constitutions
Comparing the legislatures
The legislatures differ in power and relationship to the executive:
- The US Congress is co-equal (House and Senate both powerful, with the Senate holding strong exclusive powers) and separate from the executive, so it can be controlled by a different party (divided government).
- The UK Parliament has a dominant elected Commons and a subordinate Lords, and the executive sits in and controls it through a majority and the whips.
- Similarities: both are bicameral, both represent constituencies and scrutinise the executive, and both can be hampered by partisanship.
The structural approach explains why the US legislature checks the executive more (separation of powers) while the UK executive dominates Parliament (fusion). A rational lens adds that members of Congress, facing constant re-election, prioritise constituency interests over party more than UK MPs do.
Comparing the executives
The president and prime minister differ in their power base:
- The president is separately elected, is both head of state and head of government, and has unilateral tools (executive orders, commander-in-chief and foreign-policy powers), but faces an independent Congress and cannot count on a legislative majority.
- The prime minister is not separately elected (they lead the largest Commons party), is only head of government, and can dominate Parliament when commanding a majority, but depends entirely on Cabinet and party support and can be removed by them.
The comparison is finely balanced: the president faces more institutional checks, but the PM can be more dominant with a secure majority, a difference the structural approach (separation versus fusion) explains best.
Comparing the judiciaries
Examples in context
- The separation versus fusion of powers, the structural root of most UK to USA executive and legislative differences.
- Divided government in the USA versus a whipped Commons majority in the UK, illustrating the contrasting executive to legislature relationships.
- The US Court striking down laws versus the UK Court's declarations of incompatibility, the key judicial contrast.
- The codified, entrenched US constitution versus the uncodified, flexible UK one, the foundation of the comparison.
Try this
Q1. Examine how the structural approach explains differences between the UK and US executives. [12 marks]
- Cue. Define the structural approach and apply the separation versus fusion of powers to explain the different constraints on the president and PM (no judgement required).
Q2. Evaluate the view that the UK and US judiciaries are more similar than different. [30 marks]
- What the marker wants. A two-sided AO1 to AO3 synoptic essay weighing shared independence against the US Court's power to strike down law, applying a comparative approach and reaching a judgement.
Exam-style practice questions
Practice questions written in the style of Pearson Edexcel exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.
Edexcel 201920 marksEvaluate the view that the US president is more constrained than the UK prime minister. Reworded from a 30-mark Section C synoptic essay to fit the schema; argue both sides and reach a judgement, using a comparative approach.Show worked answer →
A Section C 30-mark synoptic essay (shown as 20), marked on AO1, AO2 and AO3, that should use a comparative approach. Build two-sided arguments and a judgement.
President more constrained: the separation of powers, checks and balances, federalism and a frequently hostile Congress limit the president, who cannot rely on a legislative majority.
PM more constrained (or president less constrained): the PM faces fewer institutional checks when commanding a Commons majority (fusion of powers), so a strong PM can dominate, while the president has unilateral tools (executive orders, foreign-policy and commander-in-chief powers).
A Level 5 answer applies a structural approach (the separation versus fusion of powers explains the difference), weighs the institutional constraints, and judges, for example, that the president faces more institutional checks but the PM can be more dominant with a secure majority.
Edexcel 202120 marksEvaluate the view that the UK and US legislatures are more different than similar. Reworded from a 30-mark Section C synoptic essay to fit the schema; argue both sides and reach a judgement, using a comparative approach.Show worked answer →
A Section C 30-mark essay (shown as 20) on AO1, AO2 and AO3, using a comparative approach. Plan balanced arguments.
More different: the US chambers are co-equal and powerful while the UK Lords is subordinate to the Commons; Congress is separate from the executive while the UK executive sits in and controls Parliament; party discipline is far stronger in the UK.
More similar: both are bicameral, both represent constituencies and scrutinise the executive, and both can be constrained by partisanship.
A Level 5 answer applies the structural approach (the separation versus fusion of powers and the equality of the chambers), weighs the differences against the similarities, and reaches a judgement that they are more different than similar.
Related dot points
- Component 3A.6.1: the three comparative theoretical approaches (rational, cultural and structural) and the different ways they explain similarities and differences between the government and politics of the UK and USA.
An Edexcel A-Level Politics Component 3 answer on the comparative theories, covering the rational, cultural and structural approaches, what each focuses on, and how they explain similarities and differences between the government and politics of the UK and USA, the compulsory focus of Section B.
- Component 3A.6.9 to 6.10: comparing and debating UK and US democracy and participation (party systems, internal party unity, party policy profiles, campaign finance and pressure groups), and how rational, cultural and structural approaches account for the differences.
An Edexcel A-Level Politics Component 3 answer comparing UK and US democracy and participation, covering the two-party and multi-party systems, internal party unity, the policy profiles of the main parties, campaign finance and party funding, and the power and methods of pressure groups, explained through rational, cultural and structural approaches.
- Component 3A.1: the nature of the US Constitution (vagueness, codification, entrenchment), its key features (federalism, separation of powers, checks and balances, bipartisanship, limited government), the amendment process and the federalism debate.
An Edexcel A-Level Politics Component 3 answer on the US Constitution and federalism, covering the codified and entrenched nature of the document, federalism, the separation of powers and checks and balances, limited government, the amendment process, and the debate over how federal the USA remains today.
- Component 3A.3: the formal and informal sources of presidential power, the relationships with Congress and the Supreme Court, the limitations on the president, and the debate over the imperial presidency, with reference to presidents since 1992.
An Edexcel A-Level Politics Component 3 answer on the US presidency, covering the formal constitutional powers and informal sources of power such as executive orders and the power of persuasion, EXOP, the relationships with Congress and the Supreme Court, the limitations on presidential power, and the debate over the imperial presidency, with reference to presidents since 1992.
- Component 1.1: the nature of the UK constitution (unentrenched, uncodified, unitary), the twin pillars of parliamentary sovereignty and the rule of law, the five main sources, and the debate over codification.
An Edexcel A-Level Politics Component 2 answer on the UK constitution, covering its uncodified, unentrenched and unitary nature, the twin pillars of parliamentary sovereignty and the rule of law, the five main sources (statute, common law, conventions, authoritative works and treaties), and the debate over codification.
Sources & how we know this
- Pearson Edexcel A-Level Politics (9PL0) specification — Pearson Edexcel (2017)