Definition
Desert, as a legal term, means to abandon a person or duty with the intention of making the separation permanent. It appears most prominently in two legal contexts:
1. Family law. The willful departure of one spouse from the other, without justification and without consent, combined with an intent not to return. In jurisdictions that retained fault-based divorce, desertion (sometimes called abandonment) was a recognized ground for divorce. The conduct required was not merely physical absence but volitional departure accompanied by the intent to sever the marital relationship permanently.
2. Military law. The unauthorized absence of a servicemember from their post or unit, coupled with intent to remain away permanently or to avoid hazardous duty. Military desertion is a distinct offense from unauthorized absence (UA) or absence without leave (AWOL), the distinguishing factor being the element of intent.
Common Language
Modern common usage (Wiktionary): Usually of a place — abandoned, deserted, or uninhabited.
Historical common usage (Webster's 1913): That which is deserved; merit or just reward; rightful claim to recompense. "According to their deserts will I judge them."
The legal term desert (verb) shares its root with the adjective meaning abandoned, but diverges entirely from the Webster's sense of merit or deserved reward. A researcher encountering "desert" in historical legal documents must determine immediately whether the source is using the term in its abandonment sense (the legal verb) or its merit sense (the common noun form still visible in phrases like "just deserts"). These are unrelated meanings that happen to share spelling, and conflation can distort the reading of older family law or moral philosophy texts embedded in legal records.
Common Confusion
Desert vs. Desertion: In legal usage, "desertion" is the nominative form in most statutes and cases; "desert" most often appears as the verb ("she deserted the marital home") or as a shorthand noun in older texts. Researchers should index and search for both forms.
Desert vs. Abandonment: These terms overlap substantially in family law but are not always synonymous. Some jurisdictions treated abandonment as the broader category, encompassing financial abandonment and child abandonment, while desertion referred specifically to spousal departure in the marital context. Historical sources may use the terms interchangeably; modern statutes often define them independently.
Just deserts vs. legal desert: The phrase "just deserts" (from the merit/reward sense of the noun) appears in sentencing philosophy and retributive justice theory. It has no structural relationship to desert as abandonment. Both terms surface in legal literature, and the spelling overlap creates search noise.
Why It Matters in Research
Fault-based divorce records are the primary habitat of this term. Prior to no-fault divorce reform — which swept through U.S. jurisdictions beginning in the early 1970s — desertion was one of the standard enumerated grounds for divorce in most states. Pleadings, court opinions, and domestic relations treatises from the nineteenth and early twentieth centuries use "desert" and "desertion" with technical precision, and the elements varied by jurisdiction: some required a fixed period of absence (commonly one to five years), others required proof of intent from the outset.
Researchers working in historical family law records should note that the required duration of desertion before a divorce could be filed was jurisdictionally specific and changed over time within the same jurisdiction. A period stated in an 1880 case may not reflect the rule in 1920 in the same state. Cross-check statutory compilations for the applicable period.
In military law materials, the distinction between desertion and AWOL carries serious consequences — desertion historically carried the possibility of the death penalty in wartime — so the characterization of conduct in military tribunal records is legally significant and should not be read casually.
The merit-based noun form of "desert" appears in sentencing theory, particularly in materials on retributive justice and proportionality in punishment. When reading legal philosophy texts or penal reform literature, the word "desert" likely refers to what a person has earned or merited, not to abandonment. These materials will not cross-index cleanly with family law or military law uses.
Historical Dictionary Support
Black's and Burrill's are in close agreement on the core definition: to leave or quit with an intention not to return; to forsake utterly; to abandon. Burrill's adds the Latin root (deserere) and emphasizes the permanence of intent ("intention not to return") as the operative element, which Black's captures with "intention to cause a permanent separation." Both formulations center intent as the legal crux — the physical act of leaving is insufficient without the accompanying mental state.
Neither historical dictionary provides the additional family law elements that courts developed through case law — the requirements of unjustified cause, lack of consent by the other spouse, and the durational period of absence — nor do they address the military law application. Researchers relying solely on these dictionary definitions for pleading or interpretive purposes would have an incomplete picture. The dictionary entries function as starting points, not as complete doctrinal statements.
Webster's 1913, by contrast, does not engage with the abandonment meaning at all, defining "desert" exclusively in its merit/reward sense. This reflects ordinary usage of the noun form in that period, and underscores the importance of grammatical context when encountering the word in historical documents.
Jurisdictional Note
Desertion as a divorce ground was defined and regulated by state statute, with durational requirements varying widely — commonly one, two, or three years of continuous absence. Several states distinguished between "constructive desertion" (where one spouse's conduct forced the other to leave) and actual desertion. Most U.S. jurisdictions eliminated fault grounds as the exclusive basis for divorce following adoption of no-fault frameworks, though some retain fault grounds as optional pleading options affecting property or support outcomes.
Encyclopedia Cross-Reference
Divorce — Fault-Based Grounds (Adultery, Cruelty, Desertion, Imprisonment), The Law Mind Family Law Encyclopedia