How have courts defined 'patently illegal' orders under military case law?
Executive summary
Courts have treated a “patently illegal” military order as a narrow exception to the ordinary presumption that orders are lawful: it is an order whose criminality is so plain that “a person of ordinary sense and understanding” would know it to be unlawful, or an order actually known by the accused to be unlawful [1] [2]. That standard draws a bright line around egregious crimes—attacks on civilians, torture, falsifying records—while leaving many contested or complex commands within the presumption of lawfulness and practical deference to commanders and military judges [3] [4].
1. The baseline rule: presumption of lawfulness and the MCM carve‑out
Military law starts from an inference that orders are lawful and that disobedience is perilous; the Manual for Courts‑Martial disavows that inference only for a “patently illegal order, such as one that directs the commission of a crime” [3] [5]. That textual framework—embedded in the UCMJ and the MCM—creates a legal architecture in which “patently illegal” is an exception designed to protect soldiers from manifest criminality while preserving command authority over the vast majority of battlefield and garrison decisions [3] [6].
2. The judicial test: obviousness to an ordinary person
Federal military appellate decisions, most prominently the litigation around Lieutenant William Calley from My Lai, articulated the touchstone: an order is patently illegal if “a man of ordinary sense and understanding would, under the circumstances, know [it] to be unlawful,” or if the subordinate actually knew it to be unlawful [1] [2]. This “ordinary person” formulation ties the doctrine to objective obviousness rather than requiring specialized legal analysis, meaning that an order must be flagrantly criminal on its face to qualify [2].
3. Concrete examples and the outer boundary of the doctrine
Courts and practitioners point to paradigmatic crimes—deliberate attacks on civilians, torture, ordering soldiers to shoot unarmed noncombatants, falsification of official records—as crossing the “manifestly unlawful” or “patently illegal” line [4] [7]. The My Lai/Calley litigation remains the canonical illustration used across guidance and commentary: where the order plainly required criminal conduct (killing unarmed civilians), the defense that one “was only following orders” fails because the illegality was evident [7] [4].
4. Who decides, when, and what burden applies
Whether an order is lawful is a question of law for the military judge to decide, but that determination usually happens only after a servicemember refuses and the issue is litigated in court‑martial or tribunal [7]. The practical implication is stark: absent immediate clarity, subordinates face disciplinary risk for disobedience because lawfulness is presumed; only “patently illegal” commands absolve a refusal without risking Article 92 charges [3] [5].
5. Limits, unresolved hard cases, and the politics of clarity
Scholars and advocates warn that the “patently illegal” standard is purposefully narrow and leaves numerous “hard cases” unresolved—orders that implicate complex rules of engagement, statutory authority, or the jus ad bellum rarely qualify as patently illegal because they require legal or factual judgment [3] [6]. That gap has prompted advocacy and public messaging—campaigns and billboards urging troops to “Obey Only Lawful Orders” and advising them to seek counsel—reflecting both a push to raise awareness and an implicit agenda to shift responsibility onto service members amid political controversies over deployments [8]. Commentators urge care: the law expects refusal only when the illegality is clear and well known; it is not a general license to disobey disputed or unwise commands [6] [2].