Definition
An adverb appearing in legal instruments, oaths, jury instructions, and statutory language to indicate that a duty or obligation is to be performed with genuine moral seriousness, careful attention, and fidelity to one's honest judgment or belief. When a juror swears to "conscientiously" consider the evidence, or a statute requires an official to "conscientiously" discharge a duty, the word signals more than mere compliance — it calls for engaged, good-faith performance that reflects the actor's sincere convictions rather than rote or perfunctory action.
In jury contexts specifically, the term carries a constitutional dimension: a juror who cannot conscientiously follow the law as instructed may be subject to challenge for cause, while a juror who claims to conscientiously hold a belief — such as opposition to the death penalty — triggers inquiry into whether that belief would substantially impair performance of the juror's duties.
Common Language
Modern common usage (Wiktionary): "In a conscientious manner; attentively."
Historical common usage (Webster's 1913): "In a conscientious manner; as a matter of conscience; hence; faithfully; accurately; completely."
The common and legal meanings are closely aligned in tone, but the legal context sharpens the stakes. In ordinary speech, acting conscientiously is a virtue. In legal usage, the word does functional work: it sets the standard against which performance is measured and — particularly in oath and juror qualification contexts — defines the threshold between acceptable and disqualifying conduct.
Why It Matters in Research
Researchers encounter this term most often in three clusters of legal material: (1) juror oath and voir dire records, where courts assess whether a prospective juror can conscientiously apply the law; (2) conscientious objector doctrine, where statutes and case law require that a claimant's beliefs be sincerely and conscientiously held; and (3) fiduciary and public officer contexts, where duties are framed as requiring conscientious discharge.
The word is a quality marker, not a defined term, which means it rarely appears in statutory definitions sections. Researchers searching historical sources should expect to find it embedded in oath formulas, jury charges, and administrative regulations rather than in glossaries or headnotes. Its legal weight is contextual: the same word in a juror's oath and in a treatise on fiduciary duty is doing related but distinct work.
A significant trap in historical research: the intensity of "conscientiously" has shifted. Nineteenth-century legal usage often paired the word with "accurately" and "completely," suggesting thoroughness of process. Modern usage in constitutional law — especially post-Witherspoon doctrine on death-qualified juries — emphasizes sincerity of belief as the operative question. A researcher reading an 1870s jury charge should not assume the word carries the same freight as in a 1990s federal voir dire.
Jurisdictional variation matters in conscientious objector research. Federal selective service law has its own developed meaning of "conscientiously held belief," while state-level analogues (such as vaccine exemptions or professional licensing accommodations) use the term in ways that may or may not track federal doctrine.
Historical Dictionary Support
Rapalje & Lawrence do not provide a substantive entry for "conscientiously," and the entry attributed to this term in the source material appears to be a cataloging error — the text ("these two conjunctions are often read the one for the other. See AND; OR") belongs to a different entry entirely and has no bearing on "conscientiously." Researchers should treat the Rapalje & Lawrence source as silent on this term.
The absence of a dedicated entry in Rapalje & Lawrence is itself informative. Late nineteenth-century legal dictionaries generally treated adverbs of this kind as carrying their plain English meaning into legal usage without modification, leaving the contextual legal work to be done by courts and commentators rather than lexicographers. Webster's 1913 captures the operative sense well — faithful, accurate, complete performance as a matter of conscience — and that understanding aligns with how courts of the same era used the word in jury and oath contexts.
Jurisdictional Note
In federal constitutional law, "conscientiously" in the juror qualification context is closely tied to the Witherspoon line of cases addressing death-qualified juries. State courts vary in how rigorously they track federal standards when applying analogous language in their own jury charges and statutes. In conscientious objector and religious accommodation contexts, state law may use "conscientiously" more expansively or more narrowly than federal doctrine.
Encyclopedia Cross-Reference
See Law Mind Encyclopedia entries on Juror Qualifications, Oath, and Conscientious Objection for extended treatment of the contexts in which this term carries the most legal weight.