The US Constitution

The US Constitution is a single written document, drafted at the Philadelphia Convention between May and September 1787 and signed on 17 September 1787. New Hampshire became the ninth state to ratify in June 1788, and the Constitution took effect on 4 March 1789. Fifty-five delegates attended; thirty-nine signed.

Its most striking feature is brevity. The original text runs to roughly 4,500 words — shorter than this lesson — and is organised into just seven articles.

Article	What it does
I	Creates Congress and lists its powers (Section 8)
II	Creates the presidency and defines executive power
III	Creates the Supreme Court and the federal judiciary
IV	Governs relations between the states and their admission
V	Sets out the amendment process
VI	Makes the Constitution and federal law supreme over state law
VII	Set the terms for ratification in 1787–89

The document is codified: the rules that create and limit US government sit in one authoritative text, so a citizen can read what the government may and may not do. This has three consequences examiners look for.

• Higher law. The Constitution outranks any statute. A law that conflicts with it is void.
• Judicial supremacy over meaning. Someone must decide what the words require. Since Marbury v Madison (1803) that has been the Supreme Court, through judicial review — a power the text does not actually grant.
• Symbolic authority. Politicians of both parties argue about what the Constitution means, not whether it binds them.

Codification is about form — the rules are in one place. Entrenchment is about protection — the rules are hard to change. The US Constitution has both; the UK's has neither. Keep the two ideas apart.

Entrenchment means the Constitution cannot be amended by ordinary legislation. Article V demands supermajorities most Congresses cannot assemble, so the document is protected from a temporary majority. Since 1789 more than 11,000 amendments have been introduced in Congress and 27 have been ratified — ten of them together, as the Bill of Rights, in December 1791.

Entrenchment produces a second-order effect: because formal change is so difficult, the Constitution evolves mainly through interpretation. And interpretation is possible only because the text is vague.

Three examples of that vagueness, each of which has generated decades of litigation:

Clause	Wording	What is unclear
Necessary and proper (Art I, s8)	Congress may make laws "necessary and proper" for carrying out its listed powers	Does "necessary" mean indispensable, or merely convenient?
Commerce clause (Art I, s8)	Congress may regulate commerce "among the several States"	How remote can an activity be from interstate trade and still be regulated?
Advice and consent (Art II, s2)	The President appoints judges "by and with the Advice and Consent of the Senate"	Must the Senate hold a vote at all?

Worked example — how vagueness created a whole category of federal power. In 1816 Congress chartered a national bank. Nothing in Article I lists a power to create banks. Maryland taxed the Baltimore branch, arguing Congress had exceeded its enumerated powers. In McCulloch v Maryland (1819) Chief Justice Marshall read "necessary and proper" broadly: a bank was a legitimate means of exercising the enumerated powers to tax, borrow and coin money. The ruling invented implied powers, and the elastic clause has been the constitutional basis for federal expansion — from the New Deal to modern healthcare regulation — ever since.

The consequence for the exam is that the Constitution's meaning is a live political question. Originalists argue the text means what it meant in 1787; advocates of a living Constitution argue it must be read against present conditions. That disagreement is why Supreme Court appointments are fought so hard.

Articles I to III hand each branch its own powers, personnel and premises. The distribution is deliberately uneven: Congress is described first and at greatest length, and its powers are the only ones set out as a list.

Branch	Article	Core constitutional powers
Legislature (Congress)	I	Tax and spend; borrow; regulate interstate and foreign commerce; coin money; declare war; raise and maintain armed forces; make all laws "necessary and proper" to these ends
Executive (President)	II	Commander-in-chief; make treaties (with two-thirds of the Senate); nominate judges, ambassadors and executive officers; grant pardons; veto legislation; "take Care that the Laws be faithfully executed"
Judiciary (Supreme Court)	III	Hear cases arising under the Constitution, federal law and treaties; life tenure "during good Behaviour"; salary protected from reduction

Two features of this framework matter more than the lists themselves.

Article I is a list; Article II is a sentence. Congress's powers are enumerated — spelled out and therefore bounded. The President's are introduced by a single vesting clause ("The executive Power shall be vested in a President"), which modern presidents have used to claim broad inherent authority in national security and emergency management. The vagueness of Article II is the constitutional root of the imperial presidency debate.

Article III does not mention judicial review. The Supreme Court's central power — declaring an act of Congress or the President unconstitutional — was asserted by the Court itself in 1803 and has been accepted since. The most powerful check in the system is not written down.

Article V creates a two-stage process. An amendment must first be proposed, then ratified, and each stage has two possible routes.

Stage	Route A (used for all 27)	Route B
Proposal	Two-thirds of both houses of Congress	A national convention called by two-thirds of state legislatures (34 states) — no amendment has yet reached the Constitution by this route
Ratification	Three-quarters of state legislatures (38 of 50)	Ratifying conventions in three-quarters of states — used once, for the 21st Amendment in 1933

Worked example 1 — an amendment that succeeded in 100 days. During the Vietnam War, men could be conscripted at 18 but could not vote until 21. The 26th Amendment, lowering the federal voting age to 18, was proposed by Congress on 23 March 1971 and completed ratification on 1 July 1971. It moved so fast because the injustice was easy to state, it cost no state anything, and neither party could be seen to oppose it.

Worked example 2 — an amendment that failed. The Equal Rights Amendment, guaranteeing equality of rights regardless of sex, passed Congress on 22 March 1972 with a seven-year ratification deadline, later extended to June 1982. Thirty-five states ratified — three short of the 38 required — and five states voted to rescind. Nevada (2017), Illinois (2018) and Virginia (2020) ratified decades after the deadline expired, and whether those ratifications count remains legally contested. The ERA shows how a proposal with majority public support can still die: Article V hands a veto to thirteen states containing a small share of the population.

Advantages and disadvantages of the formal process:

Strengths	Weaknesses
Protects the Constitution from a passing majority or a single dominant party	Entrenches an eighteenth-century text against reform a clear majority wants
Forces broad, cross-party and cross-state agreement, so amendments carry real legitimacy	Thirteen states can block change, giving disproportionate power to small, rural states
Federalism is respected — states are partners in changing the rules that bind them	Blocked formal change pushes constitutional development onto nine unelected Justices
Amendments that pass tend to endure; only one has been repealed (Prohibition)	Slow: the 27th Amendment took 202 years from proposal to ratification

The 1787 design separates personnel as well as function: no person may serve in two branches at once, so a Cabinet secretary must resign a congressional seat, and the President cannot sit in Congress. That is a sharper separation than the UK, where ministers must be parliamentarians.

Separation on its own would produce three isolated branches. Checks and balances deliberately overlap them, so each needs the others' acquiescence to act.

Do the checks still work? The evidence since 2000 cuts both ways, and a strong answer uses recent cases on each side.

• Congress checking the President. Congress overrode Trump's veto of the National Defense Authorization Act, completing the two-thirds vote in both chambers on 1 January 2021 — the only override of his first term. It succeeded partly because he was days from leaving office.
• The Court checking the President. In February 2026 the Supreme Court held that Trump could not use the International Emergency Economic Powers Act 1977 to impose sweeping import tariffs, since Article I reserves taxing powers to Congress. Chief Justice Roberts, Amy Coney Barrett and Neil Gorsuch joined the three liberal Justices. In December 2025 the same six had ruled that he lacked authority to take control of the Illinois National Guard and deploy it to Chicago.
• The checks failing. Of 26 rulings on challenges to Trump administration actions during 2025, the administration won 21. And where one party holds the presidency and both chambers — as Republicans have done in the 119th Congress since January 2025 — congressional checks weaken, because the majority has little incentive to investigate its own President.

Bipartisanship is not a slogan the framers used; it is a consequence of the thresholds they set. Political parties did not exist in 1787, but by requiring more than a simple majority for the system's most consequential acts, Article I and Article V make single-party action difficult in a two-party country.

Action	Threshold	Why one party rarely clears it alone
Override a presidential veto	Two-thirds of both chambers	No party has held 290 House seats since 1979, or 67 Senate seats since 1967
Ratify a treaty	Two-thirds of senators present	Requires opposition votes in almost every Congress
Convict on impeachment	Two-thirds of the Senate	Removal is impossible on party-line votes alone
Propose an amendment	Two-thirds of both chambers	Constitutional change is effectively cross-party by design
End a Senate filibuster	Three-fifths (60 votes)	A Senate rule rather than a constitutional one, with the same effect

The design assumed cooperation. Modern partisanship frustrates it. In July 2025 the tax-cutting bill Trump called his "big, beautiful bill" passed both chambers with no Democratic votes at all: two Republicans opposed it in the House, and it cleared the Senate only when Vice-President Vance used his casting vote. Senator Mike Enzi, chairing the Senate Budget Committee during Trump's first term, declined to hold a hearing on the 2020 budget on the grounds that it would create "animosity" — an example of partisanship suppressing scrutiny rather than merely blocking legislation.

Bipartisanship has not disappeared. It survives in defence and foreign policy — the 2021 veto override was itself cross-party — and in industry-based congressional caucuses that cut across party lines. But when a constitutional design depends on cross-party agreement and the party system stops supplying it, the result is gridlock: the October 2025 federal shutdown, the fifth since 2013, began because Congress could not agree a funding bill.

The remaining two features of the 1787 design both work by subtraction — they define what the federal government may not do.

Federalism divides sovereignty between the national government and the states. The word does not appear in the Constitution; the structure is built from three provisions working together: the enumerated powers of Article I Section 8, the supremacy clause of Article VI, and the Tenth Amendment, which reserves to the states or the people every power not delegated to the federal government. Because the states existed before the union and had to agree to it, they retain authority Congress cannot simply legislate away. The scale of what remains state-level is examined in full under specification section 1.3.

Limited government is the broader principle: the federal government holds only the powers it was granted, and even those are fenced by rights. Four mechanisms enforce it.

• Enumeration. Article I lists what Congress may do, implying it may do nothing else.
• The Bill of Rights. The first ten amendments place whole subjects — speech, religion, arms, searches, criminal procedure — outside ordinary legislative reach.
• Separation of powers and checks. Power is fragmented so it cannot be assembled in one place.
• Judicial review. The Court can void an act that exceeds the limits.

How well does limited government hold in practice? The honest answer is: less well than in 1787, and unevenly.

Evidence that limits still bind	Evidence that they have eroded
The Court voided the tariff regime in February 2026 because taxation belongs to Congress	Presidents legislate in effect through executive orders when Congress is deadlocked
United States v Lopez (1995) and Printz v United States (1997) struck down federal laws for exceeding federal power	The commerce clause and elastic clause have been read expansively since the New Deal
Congress retains the power of the purse, exercised bluntly in the October 2025 shutdown	The USA PATRIOT Act 2001 expanded federal surveillance powers rapidly after a crisis
The Bill of Rights still defeats federal statutes in court	Emergency and war powers are claimed under the vague vesting clause of Article II

1. Treating codification and entrenchment as the same thing

They are separate properties. A constitution could in principle be written down in one document yet amendable by simple majority. Define both and say which one explains the difficulty of reform.

2. Describing the Constitution as "rigid" without qualification

The formal text is rigid; the working constitution is flexible. Amendment is close to impossible, so change arrives through Supreme Court interpretation, executive practice and congressional statute. The best answers explain that rigidity in one channel forces flexibility into another.

3. Using pre-2000 examples for presidential material

The specification's reference window for the US presidency runs from 2000, so build answers around George W. Bush onwards. Earlier cases such as Marbury (1803) and McCulloch (1819) are still essential — they are constitutional landmarks, not presidential examples.

4. Saying "the Constitution guarantees judicial review"

It does not. Article III creates the Court but is silent on the power to strike down legislation, which the Court claimed for itself in Marbury v Madison (1803). Asserting the opposite is a factual error examiners notice.

5. Listing checks and balances without evidence that they worked or failed

A list of powers is AO1 only. Attach an outcome and a date to each: the 1 January 2021 veto override, the February 2026 tariffs ruling, the December 2025 National Guard ruling, the failure of the Senate to convict at either Trump impeachment trial.

6. Confusing "the principles" with "the branches"

Specification section 1.2 names four features: federalism, separation of powers and checks and balances, bipartisanship, and limited government. A question on the principles is not answered by describing Articles I to III.

7. Reaching no judgement on effectiveness

The 30-mark command word is Evaluate, and AO3 carries a third of the marks. State whether the 1787 design still constrains government today, and justify the verdict with the strongest evidence on the other side acknowledged.