Montesquieu Warned That Liberty Dies Where One Hand Makes and Enforces Law

Here is a riddle for the next civics bee. Which man, born in a French castle, who held a hereditary judgeship he later sold, who grew wine for the English market and never set foot in America, did more than any other foreigner to design the American government? He was not a soldier. He was not a revolutionary. He was a baron who liked to read in a tower library and who wrote in his private notebooks that he had never known a sorrow an hour of reading could not relieve.

His name was Charles-Louis de Secondat, baron de La Brède et de Montesquieu. In 1748 he published The Spirit of the Laws, and forty years later James Madison, defending the new Constitution in Federalist 47, called him "the oracle who is always consulted and cited on this subject." The subject was the separation of powers. If you have ever been grateful that the people who write the law are not the people who arrest you under it, and not the people who sit in judgment when you are tried, you owe a debt to a man from Bordeaux.

The life: castle, court and vineyard

Montesquieu was born on January 18, 1689, at the Château de La Brède, a moated medieval castle south of Bordeaux. The year matters. 1689 was the year England's Parliament passed its Bill of Rights after the Glorious Revolution, and the same year John Locke's Two Treatises came off the press. The man who would explain the English constitution to the world was born in the season it was being settled.

He studied law, and in 1716 he inherited from an uncle both the name Montesquieu and the office of président à mortier in the Parlement of Bordeaux. In the France of that era a parlement was not a legislature but a high court, and judicial offices were property that could be bought, sold and inherited. That detail is worth holding on to. Montesquieu spent a decade as a judge in a system where the courts belonged to families, the king made law by decree, and the line between making, enforcing and judging law was blurred wherever the crown wanted it blurred. He sold the office in 1726. He knew from the bench what concentrated power looked like.

He was also a man of business. The estate at La Brède produced wine, and Montesquieu sold a good deal of it to English buyers. A philosopher who understood commerce from the inside is rarer than he should be, and it shows in his writing.

His first fame came in 1721 with the Persian Letters, published anonymously, a satire in which two Persian travelers write home about the absurdities of Paris: the vanity of the court, the quarrels of the clergy, the fashions that changed weekly. It was the eighteenth-century version of following a bad idea one step further than its fans do, and Paris loved it. He was elected to the Académie française in 1728.

Then he traveled, from 1728 to 1731, through Austria, Hungary, Italy, Germany and Holland, and finally to England, where he spent roughly a year and a half. He attended debates in Parliament, was elected to the Royal Society, and watched a free people argue loudly about its government without anyone being hauled off to the Bastille. He came home convinced that the English had found something the rest of Europe had lost.

He spent most of the next seventeen years on one book. The Spirit of the Laws appeared in Geneva in 1748, without his name on the title page, and it ran to thirty-one books in two volumes. The Catholic Church placed it on the Index of Prohibited Books in 1751. He died in Paris on February 10, 1755, nearly blind, having spent his last years answering critics.

Book XI and the English constitution

The heart of the American inheritance is Book XI, and in particular its sixth chapter, "Of the Constitution of England". Montesquieu sets up the problem in chapter 4 with a sentence that could serve as the first premise of every conservative argument about government. Constant experience shows, he says, that every man invested with power is apt to abuse it and to carry his authority as far as it will go. The remedy follows: power must be a check to power, so arranged by the nature of things that no one is compelled to do what the law does not require.

Then, in chapter 6, he divides the powers of government into three: the legislative, the executive, and the power of judging. And he states the principle that Madison would later call the definition of tyranny. In Thomas Nugent's English translation of 1750, the passage reads:

When the legislative and executive powers are united in the same person, or in the same body of magistrates, there can be no liberty; because apprehensions may arise, lest the same monarch or senate should enact tyrannical laws, to execute them in a tyrannical manner.

He goes straight on: there is no liberty if the judging power is not separated from the legislative and the executive. Join it to the legislative, and the life and liberty of the subject are exposed to arbitrary control, because the judge would then be the legislator. Join it to the executive, and the judge might behave with the violence of an oppressor. And if one man or one body exercised all three powers, all would be lost.

Notice what kind of liberty Montesquieu means. In the same book he defines political liberty in the citizen as a tranquillity of mind arising from the opinion each person has of his own safety. Liberty is not doing whatever you like. It is the confidence that you will not be destroyed by the people who hold power, because they cannot make a rule, enforce it and judge your guilt all at once. A free man sleeps well.

Laws must fit a people

Montesquieu's book is not only about the separation of powers. Its title is a thesis. The laws of a nation, he argues, are not a geometry exercise that can be imposed on any people at all. They must suit the people for whom they are made: their religion, their customs, their commerce, their history, their manners. Book XIX describes the "general spirit" of a nation, formed by many causes, and warns lawgivers not to change by laws what ought to be changed by manners.

Some of this is dated. Montesquieu spends pages on the influence of climate on character, theories no one takes seriously now. But the core insight is a conservative one, and it anticipates Burke by four decades: a constitution is not a blueprint dropped from the sky but a garment that must fit the body that wears it. The American Founders took that lesson. They did not invent a government from nothing. They built on colonial charters, English common law, the habits of town meetings and county courts, and more than a century of self-government in their own assemblies. The new Constitution was radical in its design and familiar in its materials.

Commerce as a softener of manners

Book XX makes an argument that the modern left has forgotten and the modern right should remember. Commerce, Montesquieu says, cures destructive prejudices, and it is almost a general rule that wherever manners are gentle there is commerce, and wherever there is commerce, manners are gentle. The natural effect of commerce is to lead to peace, because two nations that trade with each other become mutually dependent.

This is the idea historians call doux commerce, gentle commerce. It is not a claim that merchants are saints. Montesquieu notes that commerce can corrupt pure morals even as it polishes barbarous ones. It is a claim that a society built on voluntary exchange teaches habits of trust, punctuality, calculation and cooperation with strangers, habits a society built on conquest does not. The moral side of that argument is explored in Markets Reward Serving Strangers, and That Is a Moral Achievement. A vineyard owner who sold to English merchants while England and France were frequently at war knew the point firsthand.

How the Americans used him

The Founders read Montesquieu constantly. A well-known study of American political writing from 1760 to 1805 found him cited more often than any other secular author in the period. State constitutions written during the Revolution put his principle in plain words. The Massachusetts Constitution of 1780, drafted chiefly by John Adams, declares that the legislative department shall never exercise the executive and judicial powers, or either of them, and so on for each branch, "to the end it may be a government of laws and not of men."

The federal Constitution of 1787 does the same thing by architecture rather than by declaration. Article I opens, "All legislative Powers herein granted shall be vested in a Congress of the United States". Article II opens, "The executive Power shall be vested in a President of the United States of America." Article III opens, "The judicial Power of the United States, shall be vested in one supreme Court, and in such inferior Courts as the Congress may from time to time ordain and establish." Three articles, three vesting clauses, three hands.

When the Anti-Federalists charged that the new plan violated Montesquieu, because the president could veto laws and the Senate shared in appointments and treaties, Madison answered in Federalist 47. Montesquieu, he argued, did not mean that the branches should have no partial agency in each other's acts. The British constitution he admired was itself full of such blending. What Montesquieu meant was that where the whole power of one department is exercised by the same hands which possess the whole power of another, the fundamental principles of a free constitution are subverted. That is why the Constitution separates the powers and then lets them check each other, as explained in Federalist 47 Defines Tyranny as All Powers Gathered Into the Same Hands.

Where the Americans departed from him

An honest profile has to say where the students left the teacher, and there are four places.

1. The size of a republic. Montesquieu taught, in Book VIII, that a republic must have a small territory or it cannot survive. The Anti-Federalists quoted this against the Constitution relentlessly, as the side-by-side in Federalists Versus Anti-Federalists on Six Questions, Side by Side shows. Madison turned it upside down in Federalist 10: a large republic, he argued, takes in a greater variety of parties and interests, making it less likely that a majority will share a motive to invade the rights of others. The full case is in Federalist 10 Explains Why a Large Republic Tames Faction Best. Hamilton, in Federalist 9, pointed out that Montesquieu himself had praised the confederate republic as a way to combine the advantages of small and large states.

1. Nobility. Montesquieu's English model gave a house of the legislature to a hereditary nobility, and he regarded intermediate ranks as a barrier against despotism in a monarchy. The Americans would have none of it. Article I, Section 9 says flatly, "No Title of Nobility shall be granted by the United States". The Senate would be the steadying chamber, chosen originally by state legislatures, not by birth.

1. The judiciary. Montesquieu wrote that of the three powers, the judging power is in some measure next to nothing. Hamilton quoted that line in a footnote to Federalist 78 to argue the judiciary is the least dangerous branch, but the Americans then gave their courts something Montesquieu never imagined: a written constitution to enforce against the other two branches, a power Chief Justice Marshall made explicit in Marbury v. Madison (1803). The reasoning is read line by line in Neither Force Nor Will, Hamilton's Federalist 78 Read Line by Line.

1. Federalism. Montesquieu divided power horizontally. The Americans divided it vertically too, between the national government and the states, which Madison in Federalist 51 called a double security for the rights of the people. That second separation is an American invention.

The strongest objection: separation is a recipe for paralysis

The best case against Montesquieu's system is an old one, and it was made most forcefully by an American. In Congressional Government, published in 1885, a young political scientist named Woodrow Wilson argued that the separation of powers fractured responsibility. Nobody could be held accountable because everybody could blame somebody else. Parliamentary systems, he said, fuse the executive and legislative powers in a cabinet that answers to a majority, and so they get things done and voters know whom to reward or punish. The modern version is familiar: gridlock, shutdowns, a Congress that cannot pass a budget on time, a country that cannot act quickly when it must.

Let us take it seriously and answer it.

• Efficiency is not the goal. Montesquieu's whole premise is that power is apt to be abused. A government designed for speed is designed for speed in both directions: it can do great harm as quickly as great good. The founders chose friction on purpose, so that a law must win a majority in two chambers and a president's signature, or a supermajority over his veto, before it binds three hundred million people.
• Accountability survives. Voters can and do punish divided government. They change the House every two years, a third of the Senate every two, and the presidency every four. What they cannot do is see one transient majority remake everything in a single season.
• The alternative concentrates power where Montesquieu feared it most. The modern administrative agency writes rules, enforces them and adjudicates violations before its own judges. That is all three powers in one body of magistrates, the arrangement Book XI says leaves no liberty. The Supreme Court's recent decisions, including Loper Bright Enterprises v. Raimondo (2024), which ended judicial deference to agency readings of ambiguous statutes, are a partial return to his principle.
• Gridlock is often the system working. When a nation is closely divided, a government that cannot act boldly is reflecting the people accurately. That argument is made in Gridlock Is the Constitution Working, Not the Constitution Failing.

Wilson's critique, followed one step further, asks us to trade the tranquillity of mind Montesquieu defined as liberty for the convenience of whoever wins the next election. That is a bad trade for anyone who expects to lose an election someday, which is everyone.

What to learn from the baron

Montesquieu did not write for Americans, but he wrote as if he expected someone to build what he described. Three lessons last.

First, distrust power as such, including power held by people you agree with. Every man invested with power is apt to abuse it, not only the other party's men. Second, make laws that fit the people, and change customs by persuasion rather than by decree. Third, value commerce for what it does to character: a nation of traders learns to deal with strangers on terms of trust, and that is no small thing.

And when someone in Washington proposes to let one agency write a rule, enforce it and sit in judgment on those accused of breaking it, recall the judge from Bordeaux who sold his own office, and his sentence that in such a case there can be no liberty.

The case in brief

1. Montesquieu, a Bordeaux judge, vineyard owner and satirist, published The Spirit of the Laws in 1748 after studying England's government firsthand.
2. Book XI taught that liberty is lost when the same hands make, enforce and judge the law, because every man invested with power is apt to abuse it.
3. He also taught that laws must fit a people's character and that commerce softens manners, lessons the Founders absorbed.
4. The Americans adopted his separation of powers in three vesting clauses, then departed from him on the size of a republic, nobility, judicial power and federalism.
5. The charge that separation causes paralysis mistakes speed for good government; an agency that writes, enforces and judges its own rules is exactly what he warned against.

What you can do: read the first sentence of Articles I, II and III on our Constitution page, then look up one federal agency that both writes rules and runs its own in-house hearings, and ask your senator whether Congress should move those hearings to real courts.