Definition
EMISSION carries two distinct meanings in legal contexts, separated by field and era:
1. Medical-Legal / Criminal Law (historical): The expulsion or ejection of any matter from the body, most commonly referenced as the emission of semen or urine. This usage appears almost exclusively in the context of sexual offense law, particularly rape prosecutions, where courts historically debated whether proof of seminal emission was required to establish the completed offense.
2. Environmental / Regulatory Law (modern): The discharge or release of pollutants, gases, particulates, or other substances into the atmosphere or environment from a defined source. Statutes such as the Clean Air Act establish regulatory frameworks built around this meaning, defining permissible emission levels, emission standards, and tradeable emission allowances.
The two meanings share only the most general sense of "something expelled or released." A researcher encountering EMISSION in pre-twentieth-century legal sources should default to meaning (1); in post-1960s regulatory or environmental materials, meaning (2) governs.
---
Common Language
Modern common usage (Wiktionary): The act of emitting; sending forth or putting into circulation. Also, something which is emitted or sent out.
Historical common usage (Webster's 1913): The act of sending or throwing out; the act of sending forth or putting into circulation — as in the emission of light, heat, or bank notes. Also used for that which is sent out at one time, as a single issue or discharge.
Editorial note: The common meaning of emission is broad and neutral — light, heat, currency, gases all "emit." The historical legal meaning was far narrower, confined almost entirely to bodily expulsion in the criminal law context. The modern regulatory legal meaning aligns more closely with the common meaning but adds a specifically environmental and statutory dimension: an emission is not just anything discharged, but a discharge subject to measurement, permitting, and governmental control.
---
Recognized Forms
/ SUBTYPES
In modern environmental law, EMISSION appears in several formal regulatory configurations:
- Point source emission: Discharge from an identifiable, fixed source such as a smokestack or exhaust pipe.
- Non-point source emission: Diffuse discharge not attributable to a single outlet, such as agricultural runoff or vehicle fleet exhaust considered in aggregate.
- Fugitive emission: Unintentional or uncontrolled release not passing through a stack or vent — a category with specific regulatory treatment under the Clean Air Act.
- Greenhouse gas emission: Release of carbon dioxide, methane, or other gases contributing to climate forcing; subject to its own evolving regulatory and treaty frameworks.
---
Why It Matters in Research
Researchers face a sharp temporal and doctrinal split with this term. In any legal source predating the mid-twentieth century, EMISSION is almost certainly a medical-jurisprudence term embedded in criminal law, not an environmental one. Searching historical case reporters, treatises, or digests for EMISSION without that context will produce exclusively criminal law results — predominantly rape and sexual offense cases — which may be entirely irrelevant to a modern environmental research project, and vice versa.
For criminal law historians: the emission-of-semen question in rape law was a live doctrinal dispute through much of the nineteenth century. English common law authorities including Hale's Pleas of the Crown treated emission as an element of the offense; courts and legislatures progressively abandoned that requirement. Primary sources will show a gradual retreat from emission as a required element, often through statutory amendment. Researchers tracing this evolution should track not just case law but changes to statutory definitions of rape and penetration.
For environmental law researchers: the term EMISSION does not appear as a legal term of art in any of the major historical dictionaries in this corpus — Black's, Bouvier's, and Rapalje & Lawrence all address only the medical-jurisprudence meaning. This is an important absence: it confirms that EMISSION as an environmental concept is entirely a product of twentieth-century regulatory law, not a transplant from common law doctrine. Do not expect historical dictionary support for the regulatory meaning; look instead to statutory text, agency rulemaking, and post-1970 case law.
The corpus connections are essentially non-overlapping: the criminal law meaning lives in nineteenth-century treatises and case digests; the regulatory meaning lives in administrative law, environmental statutes, and agency guidance documents.
---
Historical Dictionary Support
All four source dictionaries — Black's (both editions), Bouvier's, and Rapalje & Lawrence — define EMISSION exclusively in its medical-jurisprudence sense. There is strong agreement across these sources: emission means expulsion of matter from the body, and the legal significance lies in rape prosecution.
The most instructive entry is Bouvier's, which states directly that "emission is not necessary in the commission of a rape to complete the offence" and cites a substantial run of English and American authority for that proposition. This reflects the state of law at the time of publication — the old requirement had been substantially discarded. Rapalje & Lawrence makes the same point more tersely: "At one time it was supposed that it was essential to prove emission of semen on the trial of indictment for rape, but no such evidence is now required."
What the historical dictionaries miss entirely: the modern regulatory and environmental meaning of EMISSION does not appear anywhere in these sources. This is not an oversight to be corrected by inference — it is a genuine historical boundary. The legal concept of controlled environmental emission simply did not exist as a discrete legal category when these dictionaries were compiled. Researchers must supply modern statutory and regulatory sources to fill this gap.
---
Jurisdictional Note
In modern environmental law, emission standards and definitions are set at both the federal level (Clean Air Act and EPA regulations) and the state level, and the two frameworks interact through mechanisms such as State Implementation Plans. Definitions of "emission" for regulatory purposes can vary meaningfully between federal rules and state programs, particularly for greenhouse gases and mobile source regulation.
---
Encyclopedia Cross-Reference
See Law Mind Encyclopedia: Environmental Regulation (for modern statutory and regulatory emission frameworks); Criminal Law — Sexual Offenses (for the historical medical-jurisprudence meaning and its role in rape law).
---