History of Criminal Law: From Hammurabi to the Model Penal Code

The history of criminal law spans roughly four thousand years, from the earliest written codes of ancient Mesopotamia through Roman public prosecutions, medieval ordeals, Enlightenment reform, nineteenth-century codification, and the constitutional and international frameworks that shape justice today. Its arc runs in one broad direction: away from private vengeance and arbitrary power, toward written rules, proportionate punishment, and procedural protections for the accused. The path has never been straight, and every era has borrowed, revised, and reacted against what came before.

The First Written Codes

Writing came before law codes, but not by much. The Code of Ur-Nammu, produced by the Sumerian ruler of Ur in the twenty-first century BCE, is the oldest surviving written law.¹ The Code of Lipit-Ishtar from the city of Isin followed, and both preceded the more famous Code of Hammurabi by up to two centuries.

Hammurabi, king of Babylon from 1792 to 1750 BCE, had 282 case laws inscribed on a diorite stela. The code covered prices and trade, marriage and divorce, and criminal matters such as assault and theft.² Several of its features shaped what would come later. Punishment was tied to the harm caused under the principle of lex talionis, the familiar “eye for an eye,” and penalties varied by the social class of both offender and victim. Knocking out the teeth of a social equal carried a different consequence than knocking out the teeth of someone of lower rank.¹

The code also contained early procedural safeguards. The burden of proof rested on the accuser: someone who brought a capital charge and could not prove it faced the death penalty. Judges who ruled improperly paid twelve times the original fine and were removed from the bench permanently.³ When evidence was thin, the code turned to trial by ordeal — a leap into a river, with survival taken as proof of innocence. Crude by modern standards, this was still a decisive step past private blood feud toward public, written justice.²

Rome and the Birth of Public Crimes

Rome contributed a distinction that runs through every modern criminal system: the split between private wrongs and public crimes. Early Roman law treated most harmful acts against individuals as private matters. Theft, bodily injury, robbery, and property damage were handled through civil actions in which the injured party sought compensation.⁴

Offenses threatening the state or the religious order were carved out as public crimes punished by the community. Treason and homicide were treated this way early on. Rome then built machinery to handle these cases: standing jury courts called quaestiones perpetuae, the first of which was created by the lex Calpurnia in 149 BCE to hear extortion cases. Roman citizens also had an early right of appeal, and the Law of the Twelve Tables around 450 BCE gave Roman society its first written rules of procedure, cutting into the arbitrary authority of magistrates.

Medieval Europe: Ordeal, Jury, and the Revival of Roman Law

After Rome fell, European law fragmented into local custom, mostly unwritten and varying from village to village. Feudalism placed judicial authority in the hands of local lords ruling from manorial courts.⁵ The Catholic Church, applying canon law compiled in works like Gratian’s Decretum of 1140, claimed jurisdiction over marriage, wills, adultery, and succession.

Guilt in serious cases was often determined by judicium Dei, the judgment of God. The accused might carry red-hot iron, plunge an arm into boiling water, or be submerged in a river, with survival or the healing of wounds read as divine verdict.⁶ The Fourth Lateran Council of 1215 formally condemned trial by ordeal, effectively forcing European courts to move toward trial by jury.⁵

The same year produced another turning point. Magna Carta placed the English king under law, and on the continent the rediscovery of Justinian’s Corpus Juris Civilis at the University of Bologna, founded around 1088, reintroduced Roman legal principles to Western Europe. Universities in Paris, Oxford, and Naples soon trained the first generation of professional lawyers.⁵

English Common Law

Anglo-Saxon England had treated most crimes as personal wrongs to be repaired by compensation to the victim.⁷ The Norman Conquest of 1066 changed the frame. Serious wrongs were reclassified as public crimes punishable by death and forfeiture of property. A centralized judiciary developed under the King’s Court at Westminster, and royal judges rode circuits to apply a uniform law that pushed aside inconsistent local customs.

Henry II’s reign from 1154 to 1189 was decisive. His Assize of Clarendon in 1166 ordered judges to travel in circuits and decide cases under laws developed at Westminster, creating what came to be called the common law.⁶ He also established juries of twelve local knights, planting the seed of the modern jury. By the thirteenth century, the royal courts at Westminster — the Exchequer, Common Pleas, and King’s Bench — held firm authority over criminal matters.⁷

Early juries were “self-informing,” drawn from the neighborhood of the alleged crime and expected to know the facts already. By the sixteenth century that had reversed: jurors were now expected to be ignorant of the case and to decide on evidence heard in court.⁸ The Marian Statutes of 1554–1555 formalized the role of justices of the peace in investigating serious crimes, binding over witnesses, and organizing prosecutions when private citizens did not.

The English division of crimes into felonies and misdemeanors also took shape in this period. Originally a felony was any offense punishable by forfeiture, mutilation, or execution; misdemeanors covered lesser offenses short of treason or felony. England abolished the distinction in 1967, substituting arrestable and nonarrestable offenses.⁹

Islamic Criminal Law

Islamic legal tradition developed on its own foundations, rooted in the Quran and the hadiths. Its most distinctive category is hudud: offenses considered violations of the rights of God, carrying fixed punishments. Traditional hudud offenses include theft, adultery, consumption of intoxicants, and highway robbery.¹⁰

In practice, the fixed penalties were applied rarely because evidentiary requirements were extremely high and a principle of avoiding punishment in cases of doubt governed. Historical records show executive suspensions of the penalties, such as Caliph Umar waiving amputation for theft during a famine. From the nineteenth century onward, Muslim-majority states moved to codify and secularize their criminal law. The Ottoman Penal Code of 1858 is widely cited as the foundational example, replacing hudud with discretionary penalties (ta’zir) such as prison sentences or fines.¹¹ Many countries, Morocco among them, keep offenses rooted in Islamic tradition while sentencing through conventional structures.

The Enlightenment Rethinking of Punishment

The eighteenth century reopened the question of what criminal law was actually for. Cesare Beccaria’s 1764 treatise On Crimes and Punishments is the starting point for nearly every modern reform argument. Writing against a background of arbitrary judicial power, torture, and wildly disproportionate sentences, Beccaria argued that punishment existed only to prevent future crime, not to inflict retribution. Certainty of a mild punishment, he wrote, deters more effectively than the threat of a harsh one, and he made early influential arguments against both torture and the death penalty.¹²

Beccaria pushed for what he called legal formalism: judges should apply the law strictly rather than reach for its “spirit,” and each crime should carry a proportionate, clearly stated punishment. Clear public codes, in his view, should replace the tangle of local custom.¹³

Jeremy Bentham built on Beccaria’s utilitarian foundation. His “moral arithmetic” grounded morals and legislation in the greatest happiness of the greatest number, and his penal theory called for punishment calibrated to just outweigh the benefit of the crime, and no more.¹² Montesquieu had supplied much of the social-contract theory underneath the reform program in Spirit of the Laws (1748), sixteen years before Beccaria, though he himself still accepted the death penalty for murderers.¹³

From the Scaffold to the Penitentiary

Before the late eighteenth century, imprisonment was rarely a punishment in its own right. Jails held people awaiting trial, execution, transportation, or corporal punishment. The punishments themselves were largely public and physical: pillories, stocks, whipping posts, branding irons that marked the offense with a letter — “T” for thief, “M” for manslaughter — and hangings.¹⁴

England’s “Bloody Code” between 1688 and 1815 expanded capital offenses from roughly fifty to more than two hundred. Stealing a silk handkerchief could, in theory, carry a death sentence. Various pressure valves kept the full severity from being applied: benefit of clergy, under which defendants could escape execution by reciting a passage from Psalm 51; jury nullification; royal pardons; and transportation of convicts, first to the American colonies and later to Australia.¹⁵

Enlightenment ideas about deterrence and proportionality fed the rise of the penitentiary. Reformers in Philadelphia and London argued that rational offenders could be reformed through solitude, labor, and reflection. Pennsylvania eliminated the death penalty for robbery, burglary, and sodomy in 1786, and by the early nineteenth century many American states had narrowed capital punishment largely to murder.¹⁵ England’s first national penitentiary, Millbank, opened in 1816. Pentonville followed in 1842, built around the “separate system” of solitary confinement.¹⁶

The twentieth century layered on more shifts. Probation entered English law in 1907. The borstal system for youth arrived in 1908. Open prisons began in 1933. Capital punishment was abolished in England under the Murder (Abolition of Death Penalty) Act 1965.¹⁶

The Positivist Challenge

The classical framework built by Beccaria and Bentham assumed a rational offender exercising free will. In the late nineteenth century, positivist criminology attacked that assumption. Italian physician Cesare Lombroso argued in his 1876 book The Criminal Man that criminal behavior was rooted in biology, and he classified the “born criminal” as an evolutionary throwback whose conduct was essentially inevitable.¹⁷

The policy implications were substantial. If crime was biological rather than chosen, punishment should aim less at retribution or deterrence and more at social protection and rehabilitation. That thinking contributed to indeterminate sentencing, under which judges tailored sentences to a defendant’s perceived dangerousness rather than fixing them to the offense. Lombroso himself proposed indefinite detention for “born criminals” beyond reform, and rehabilitative settings for offenders whose criminality he attributed to environment.¹⁷

His specific methods — measuring skulls, cataloging physical “stigmata” — were later discredited for sampling and bias problems. Biological perspectives in American criminology largely fell out of favor by the 1940s, partly because eugenicists had wielded similar ideas to devastating effect. The broader positivist claim that individual characteristics matter in explaining crime has resurfaced in contemporary biosocial criminology, which examines the interaction between genetics, neuroimaging, nutrition, and social environment.¹⁸

American Constitutional Foundations

Colonial American criminal justice was a hybrid of English legal transplants, religious orthodoxy, and local improvisation. Early Virginia’s code, imposed by the Virginia Company, mandated death for offenses as minor as stealing food or trying to flee the colony. Church attendance was compulsory, enforced by fines, whippings, or forced labor. Punishments were nearly all public and designed to shame the offender.¹⁴

The Revolution and the drafting of the Constitution produced the criminal law protections still foundational in the United States. The Bill of Rights, ratified on December 15, 1791, was authored by James Madison and drew on the Virginia Declaration of Rights, Magna Carta, and the English Bill of Rights.¹⁹ Its criminal law protections include:

Fourth Amendment: protection against unreasonable searches and seizures, and the requirement of warrants supported by probable cause.
Fifth Amendment: grand jury requirement for serious charges, protection against double jeopardy and self-incrimination, and the guarantee of due process of law.
Sixth Amendment: the right to a speedy and public trial by impartial jury, to be informed of the charges, to confront witnesses, and to the assistance of counsel.
Eighth Amendment: prohibition of excessive bail, excessive fines, and cruel and unusual punishment.²⁰

The Fourteenth Amendment, ratified after the Civil War, extended due process and equal protection to state action, providing the constitutional bridge through which Bill of Rights protections would eventually be applied against the states.²¹

Guilty Act, Guilty Mind, and the Model Penal Code

Two Latin phrases hold up much of substantive criminal law. Actus reus is the guilty act. Mens rea is the guilty mind. Both are generally required, a rule captured in a maxim attributed to Sir Edward Coke in 1603: “An act does not make a person guilty of a crime unless that person’s mind be also guilty.”²² Accidental harm without some form of culpability such as recklessness or negligence generally does not constitute a crime.

In the United States, the American Law Institute’s Model Penal Code, adopted in 1962, brought order to these ideas. The MPC drove widespread revision and codification of American substantive criminal law and standardized mens rea into four levels of culpability: purpose, knowledge, recklessness, and negligence. It is still frequently cited by courts.²³ Its influence traveled beyond the United States; MPC principles are discernible in codes from India to Canada.²⁴

The Nineteenth-Century Codification Wave

The nineteenth century saw governments around the world replacing unwritten customary law and scattered statutes with comprehensive criminal codes. The French Penal Code of 1810 was long treated as the primary engine of this movement, though recent scholarship suggests its influence has been overstated and that many national codes were continuations of existing traditions as much as they were borrowings from France.²⁵

The Indian Penal Code of 1860, drafted by Thomas Babington Macaulay under the influence of Benthamite jurisprudence, may have been the era’s most far-reaching codification. It aimed to give British India a comprehensive, precise, and accessible criminal code, and was later adopted in Pakistan, Bangladesh, Sri Lanka, Malaysia, Singapore, Brunei, and several African jurisdictions.²⁴ The IPC stayed in force in India for more than 160 years. On July 1, 2024, India replaced it with the Bharatiya Nyaya Sanhita, which introduced community service as a formal punishment, added offenses for organized crime and mob lynching, recognized transgender as a gender category, and removed the colonial-era sedition provision.²⁶

The Due Process Revolution

The mid-twentieth century brought what scholars call the due process revolution. Under Chief Justice Earl Warren, the U.S. Supreme Court constitutionalized much of criminal procedure and applied the Bill of Rights against the states. Three cases anchor the transformation.

Mapp v. Ohio (1961)

The Court had ruled in Weeks v. United States (1914) that the Fourth Amendment barred the use of illegally seized evidence in federal prosecutions, reasoning that its protections would be “of no value” otherwise.²⁷ For nearly half a century the exclusionary rule was confined to federal courts. That ended with Mapp v. Ohio in 1961. Police had entered Dollree Mapp’s home without a valid warrant and found obscene materials. In a 6–3 decision written by Justice Tom Clark, the Court extended the exclusionary rule to state courts, calling it an “essential ingredient” of the right to privacy.²⁸

Gideon v. Wainwright (1963)

Clarence Earl Gideon was charged with felony breaking and entering in Florida. Too poor to hire counsel, he asked the court to appoint a lawyer. Florida refused; state law provided appointed counsel only in capital cases. Gideon represented himself, was convicted, and got five years. He petitioned the Supreme Court from prison in his own handwriting. In a unanimous decision written by Justice Hugo Black, the Court held that the Sixth Amendment right to counsel is “fundamental and essential to a fair trial” and applies to the states through the Fourteenth Amendment.²⁹ On retrial with an attorney, Gideon was acquitted.³⁰

Miranda v. Arizona (1966)

Ernesto Miranda was arrested in Phoenix for kidnapping and rape. He confessed after a long interrogation, never having been told of his right to silence or to counsel. In a 5–4 decision issued on June 13, 1966, the Court held that the Fifth Amendment privilege against self-incrimination applies during custodial interrogation. Before questioning, police must inform a suspect of the right to remain silent, that anything said can be used against them, the right to an attorney, and the right to appointed counsel if the suspect cannot afford one.³¹ Miranda himself was retried without the confession, convicted again, and given twenty to thirty years.³²

The Miranda warnings have become one of the most recognized features of American criminal procedure. In Dickerson v. United States (2000), the Court confirmed that Miranda is a constitutional decision that cannot be overridden by statute, though later rulings have described the warnings as “prophylactic” rules rather than constitutional rights themselves.³³

From Nuremberg to the International Criminal Court

The idea that individuals, including heads of state, could be held personally accountable under international law took shape at Nuremberg. The International Military Tribunal, opened on November 20, 1945, was the first to prosecute national leaders for crimes against peace, war crimes, and crimes against humanity.³⁴ In December 1946, the UN General Assembly unanimously affirmed the principles established in the Nuremberg Charter and judgment.³⁵

Those principles sat largely dormant until the ethnic conflicts of the 1990s. The UN Security Council established the International Criminal Tribunal for the former Yugoslavia (ICTY) in 1993 and the International Criminal Tribunal for Rwanda (ICTR) in 1994. Between them, the tribunals heard thousands of witnesses and produced landmark convictions, including the ICTR’s first-ever genocide conviction against Jean-Paul Akayesu in 1998.³⁴

The permanent International Criminal Court was established by the Rome Statute, adopted on July 17, 1998, and entered into force on July 1, 2002. Based in The Hague, the ICC operates as a court of last resort under the complementarity principle, taking cases only when national courts are unwilling or unable to prosecute. It has jurisdiction over genocide, war crimes, crimes against humanity, and the crime of aggression.³⁶

Where the Law Stands Now

Criminal law in the 2020s runs on a tension between reform and reaction. On the reform side, twenty-four U.S. states have legalized recreational marijuana, Illinois abolished money bail through its Pretrial Fairness Act in 2023, and twenty-seven states plus the District of Columbia have banned juvenile life-without-parole sentences.³⁷ Several states have enacted “Clean Slate” laws to automatically seal certain criminal records, and others have restored voting rights for people with felony convictions on release from incarceration.³⁸

Restorative justice — bringing offenders, victims, and community members together to address harm outside the traditional courtroom — has expanded from niche practice into a more mainstream feature of criminal justice systems. New Zealand uses family group conferences, Northern Ireland runs restorative justice conferences, and multiple U.S. jurisdictions use restorative diversion for youth, with research associating these programs with lower reoffending rates and higher victim satisfaction.³⁸³⁹

Cutting the other way is a visible “tough on crime” resurgence. Oregon repealed its 2020 drug decriminalization measure in 2024. California voters passed Proposition 36, a penalty-enhancement measure, the same year. Alabama, Arkansas, Tennessee, and Texas have approved or requested funding for expanded prison and juvenile detention capacity.³⁸ The push and pull is not new. It echoes the cycles that have run through the history of criminal law from the start: Beccaria against the Bloody Code, rehabilitation against deterrence, the codifier against the customary judge. Each generation redraws the same argument in its own terms and hands it forward.

1
HISTORY. 8 Things You May Not Know About Hammurabis Code
2
Encyclopædia Britannica. Code of Hammurabi
3
Yale Law School, Avalon Project. Code of Hammurabi
4
Hiroshima University Repository. Roman Criminal Law
5
Encyclopædia Britannica. Medieval Law
6
The Judiciary of England and Wales. History of the Judiciary
7
Encyclopædia Britannica. Common Law
8
Yale Law School. Origins of Public Prosecution at Common Law
9
EBSCO Research Starters. Misdemeanors
10
Islamic Law Blog. Can the Severity of Ḥudūd Punishments Be Adjusted
11
Journal of Islamic Law. Moroccan Criminal Justice and Islamic Law
12
Columbia Law School. Beccaria’s On Crimes and Punishments
13
University of Oxford Faculty of Law. Beccaria Who
14
Colonial Williamsburg. Branks and Punishment in Colonial America
15
Colonial Williamsburg. Prison History
16
Howard League for Penal Reform. History of the Penal System
17
National Library of Medicine. Cesare Lombroso
18
Taylor & Francis Online. Biosocial Criminology
19
Bill of Rights Institute. Bill of Rights
20
National Archives. What Does the Bill of Rights Say
21
Constitution Annotated, Congress.gov. Fourteenth Amendment
22
vLex Canada. History of Mens Rea
23
American Law Institute. Model Penal Code
24
Jersey Law Review. The Indian Penal Code and Codification
25
Springer. The Western Codification of Criminal Law
26
LexisNexis. Reforming the Indian Penal Code
27
Justia. Mapp v. Ohio, 367 U.S. 643
28
National Constitution Center. Mapp v. Ohio
29
Justia. Gideon v. Wainwright, 372 U.S. 335
30
National Constitution Center. Gideon v. Wainwright
31
U.S. Courts. Facts and Case Summary: Miranda v. Arizona
32
Justia. Miranda v. Arizona, 384 U.S. 436
33
Constitution Annotated, Congress.gov. Fifth Amendment – Miranda
34
United States Holocaust Memorial Museum. International Criminal Justice Since Nuremberg
35
Memorium Nuremberg Trials. Birth of International Criminal Law
36
International Criminal Court. About the Court
37
Prison Policy Initiative. Winnable Criminal Justice Reforms 2026
38
The Sentencing Project. Top Trends in Criminal Legal Reform
39
Taylor & Francis Online. Restorative Justice and Criminal Law