Definition
Petit treason (also spelled "petty treason") was a category of crime in English law distinct from both ordinary murder and high treason. It consisted of the killing of a superior by a subordinate in a relationship defined by personal allegiance or duty. Three relationships qualified: a servant killing his master, a wife killing her husband, and an ecclesiastic or monk killing his prelate or lord ordinary. The offense occupied a conceptual middle ground — more serious than common murder because it violated a duty of loyalty owed to a specific superior, yet less grave than high treason, which was reserved for crimes against the sovereign and the state.
The category derived from a feudal understanding of social hierarchy: just as a subject owed allegiance to the king, a servant owed allegiance to a master, and a wife owed subjection to a husband. A killing that betrayed that bond was treated as a species of treason rather than mere homicide, and the law punished it accordingly — women convicted of petit treason were burned at the stake rather than hanged, a distinction in mode of execution that persisted long after the offense's underlying logic had become archaic.
Petit treason was abolished in England by the Offences Against the Person Act 1828 (9 Geo. IV, c. 31), after which such killings were prosecuted as ordinary murder.
Common Language
Modern common usage (Wiktionary): "The crime of a subordinate killing a superior (other than the sovereign, which would constitute high treason): a servant killing his master, a wife killing her husband, etc."
Historical common usage (Webster's 1913): Webster's 1913 does not carry a standalone entry for petit treason, treating it as a subtype of treason rather than a term requiring independent definition.
The ordinary-language understanding of "treason" — betrayal of one's country — is broad enough that a reader encountering "petit treason" might understand it as merely a lesser form of political betrayal. The legal meaning is narrower and more specific: it had nothing to do with the state, the sovereign, or political allegiance. It was entirely about the betrayal of a private, hierarchical relationship of personal duty. Researchers should not import political or constitutional connotations of "treason" when reading historical sources that use this term.
Common Confusion
Petit treason and high treason share a vocabulary but occupy entirely separate legal regimes. High treason involved crimes against the king, the royal family, or the realm — counterfeiting the great seal, levying war, compassing the sovereign's death. Petit treason was a private-law offense dressed in feudal-loyalty language. The two terms also diverged in procedure: high treason triggered attainder and forfeiture of estates; petit treason did not carry the full attainder consequences but did carry the distinctive punishment of burning for women.
Petit treason should also be distinguished from petty crime generally. The "petit" in petit treason is cognate with "petty" (small, lesser), but the offense was not treated as petty in the modern sense — it was a capital felony. The modifier meant only that it ranked below high treason in the hierarchy of betrayals.
Why It Matters in Research
Petit treason is an abolished offense, but researchers encounter it frequently in English common law sources, colonial American legal records, and early American statutory compilations. Several navigational points are essential:
First, timeline of abolition matters. English abolition came in 1828. American jurisdictions never formally received petit treason as a distinct offense in most states — Bouvier notes plainly that in the United States such a killing was treated as ordinary murder from the outset. Researchers reading colonial or early national sources should check whether the jurisdiction in question had adopted English common law on the point or treated it as surplus.
Second, gendered application. The offense as practically enforced fell almost entirely on wives and on female servants. The burning penalty for women convicted of petit treason (rather than hanging, the male default for the same offense) is a recurring subject in legal history scholarship. Sources treating the punishment without explaining this gendered dimension are incomplete.
Third, ecclesiastical dimension. Rapalje & Lawrence flags the ecclesiastical variant — a secular or religious man killing his prelate. This variant appears in some sources and not others; Burrill reduces the offense to master and husband only. Researchers tracking ecclesiastical court jurisdiction alongside this offense should consult sources that address the full tripartite form.
Fourth, the Latin tag parva proditio (small betrayal) appears in Latin legal records and some treatises. Researchers working in Latin-language sources or early Year Books should recognize this as the equivalent term.
Fifth, the corpus connection to feudal tenure and villeinage is direct. The logic of petit treason borrowed from the same hierarchical allegiance structure that organized land tenure. Entries on villeinage, serfdom, and lord-tenant relationships in the corpus provide essential context.
Historical Dictionary Support
The four source dictionaries agree on the core definition but vary in emphasis and completeness. Black's Law Dictionary provides the cleanest statement of the three qualifying relationships and cites Blackstone's Commentaries directly. Bouvier is the most practically useful for American researchers, explicitly stating that in the United States the offense was treated as ordinary murder — a crucial jurisdictional clarification that Black's omits.
Burrill reduces the offense to two relationships (master and husband) and cites 4 Bl. Com. 203, but notes abolition by 9 Geo. IV without specifying what that statute did procedurally. Rapalje & Lawrence is the most fragmented entry, but it adds the ecclesiastical dimension with a citation to Phillimore's Ecclesiastical Law, which is useful for researchers working in that area.
None of the four source dictionaries discusses the burning-at-the-stake penalty that distinguished petit treason from ordinary murder for female defendants — a significant omission given how central that punishment is to historical legal scholarship on the offense. Blackstone's Commentaries at 4 Bl. Comm. 75 and 203 remain the most complete primary source for the full doctrinal picture.
Jurisdictional Note
Petit treason as a distinct legal category was never meaningfully received in American law. Most American jurisdictions treated the conduct as ordinary murder from independence onward, and no American statute created a formal petit treason offense. Researchers should treat the term as essentially English and colonial when it appears in American sources, and verify whether any specific colonial jurisdiction purported to apply English common law rules on the point.