Definition
Post mortem (Latin: "after death") operates in law both as an adjective describing actions, proceedings, or conditions occurring after a person's death, and as a noun referring to the medical examination of a corpse to determine cause, manner, and circumstances of death.
1. As an adjective: Describes any legal act, instrument, proceeding, or condition that takes effect or arises after death. Post-mortem estate planning, post-mortem tax elections, and post-mortem disclaimers all refer to legal maneuvers executed after a decedent's death but still capable of affecting how an estate is distributed or taxed.
2. As a noun (the post-mortem): The physical examination of a dead body — also called an autopsy — conducted by a medical examiner or coroner to establish cause of death. In legal proceedings, post-mortem findings are introduced as evidence in criminal prosecutions, wrongful death actions, insurance disputes, and coroner's inquests. The term is used interchangeably with autopsy in most legal and medical contexts, though post-mortem is the older and more formally Latin-derived usage still appearing in statutes and official titles in some jurisdictions.
3. Historical procedural sense: In older English law, post mortem referred specifically to an inquisition taken after the death of a tenant in capite — a tenant who held land directly from the Crown — to determine the extent of the estate, the identity of the heir, and whether the Crown had any rights of wardship or relief. These were formal royal proceedings, not medical examinations.
---
Common Language
Modern common usage (Wiktionary): "After death" or "having been inflicted or having occurred after death." In everyday speech, post-mortem is also used colloquially to mean any after-the-fact analysis of an event or failure (e.g., a "post-mortem" of a failed project).
Historical common usage (Webster's 1913): Webster's 1913 does not appear in the provided source material for this entry, but the phrase was already in broad English usage by the nineteenth century, carrying both the Latin sense of "after death" and the specific medical sense of examination of a corpse.
The legal gap worth flagging: In ordinary speech, post-mortem has expanded to mean any retrospective analysis, entirely divorced from death. In legal contexts, the term remains anchored to actual death — either the physical examination of a body or the legal characterization of acts occurring after a specific decedent's death. A researcher encountering "post-mortem" in a legal document should not import the colloquial sense.
---
Common Confusion
Post mortem is sometimes used interchangeably with autopsy, but there is a technical distinction maintained in some forensic and statutory contexts: autopsy refers specifically to the dissection and internal examination of the body, while post-mortem examination can refer to a broader process that includes external examination, toxicology, and documentation without necessarily involving surgical dissection. For most legal research purposes the terms are functionally equivalent, but medical examiner statutes and coroner's rules in specific jurisdictions may draw the line differently.
Do not confuse post-mortem (after the death of a specific person) with post-natus (after-born), a related but entirely distinct Latin term of art appearing in the same historical sources.
---
Why It Matters in Research
Researchers face three distinct problems with this term.
First, the term does double and triple duty across legal subfields. A post-mortem in a criminal law file is a forensic autopsy report. A post-mortem in an estates file is a planning technique — a disclaimer, a qualified terminable interest property election, or a portability election — taken after death to redirect assets or reduce tax. A post-mortem in a medieval property law text is a Crown inquisition with no medical content at all. Context is everything, and a researcher cross-searching the corpus without noting the surrounding document type will conflate unrelated material.
Second, in the historical sources — including Burrill — the primary definition is the feudal inquisition meaning, not the medical one. Burrill explicitly identifies the inquisition post mortem as the established legal usage and notes the medical application as merely "now commonly applied." Modern legal usage has reversed this priority entirely: the medical examination sense is now primary, and the feudal inquisition sense is a historical artifact. Researchers working with pre-twentieth-century primary sources should expect the feudal procedural meaning to dominate.
Third, post-mortem as an adjective in estate planning creates a temporal categorization that matters for tax and property law research. Post-mortem planning tools — disclaimers, elections under the Internal Revenue Code, alternate valuation date elections — have specific deadlines running from the date of death. When researching estate administration disputes or tax controversies, locating the precise post-mortem acts taken and their timing relative to the death date is often determinative.
---
Historical Dictionary Support
Burrill's Law Dictionary leads with the feudal inquisition meaning: proceedings taken after the death of tenants in capite to determine succession rights and Crown entitlements. Burrill cites Hubback's Evidence of Succession and acknowledges the medical usage as secondary and modern. This ordering reflects the term's actual legal history — the inquisition post mortem was a formal and consequential Crown proceeding under medieval English law, not a collateral curiosity.
Burrill's entry also transitions immediately to post-natus, indicating that the historical dictionaries treated the "post-" series of Latin terms as a connected cluster of feudal and succession-related vocabulary. Researchers using Burrill for historical property law research will find this cluster useful for orienting themselves in the source material.
What Burrill does not address — and what no nineteenth-century legal dictionary could fully address — is the modern forensic and evidence-law dimension of the post-mortem examination, which developed alongside professionalized medical examination offices and coroner reform in the late nineteenth and twentieth centuries. For the forensic and evidentiary side, researchers must move to modern statutory sources, medical examiner regulations, and rules of evidence.
---
Jurisdictional Note
Terminology and institutional authority vary. Some U.S. jurisdictions use "medical examiner" systems operating under state statute with trained forensic pathologists; others retain elected coroner systems with varying requirements for medical qualification. The label "post-mortem examination" versus "autopsy" in a given jurisdiction's statute may reflect which official has authority to order or perform the procedure. Researchers working across jurisdictions should check the controlling statute rather than assuming uniform practice.
---
Encyclopedia Cross-Reference
Disclaimers as a Post-Mortem Estate Planning Tool — The Law Mind Trusts, Estates & Probate Encyclopedia (for the estate planning and tax dimension of post-mortem acts)
Post-Conviction DNA Testing — The Law Mind Criminal Law Encyclopedia (for the intersection of post-mortem forensic evidence and post-conviction proceedings)
---