Source: https://www.ucmjdefense.com/resources/defenses-special-defenses-defenses/inability-impossibility.html
Timestamp: 2019-04-19 05:03:58+00:00

Document:
The defense of inability or impossibility excuses a failure to act and is available only in situations where the accused has an affirmative duty to act, but does not.
Physical Inability. Where a defendant’s physical condition made it impossible for a defendant to act, the defendant is excused. In United States v. Cooley, 36 C.M.R. 180 (C.M.A. 1966), the defendant used inability as a defense to sleeping while on guard because the defendant suffered from narcolepsy.
United States v. King, 17 C.M.R. 3 (C.M.A. 1954). The Court held that the inability defense can be raised where the defendant who was suffering from frostbite refused an order to return to battle.
United States v. Barnes, 39 M.J. 230 (C.M.A. 1994). The Court held that the inability defense could be raised only if the defendant’s inability was not a result of his own deliberate conduct. See also United States v. New, 50 M.J. 729 (Army Ct. Crim. App. 1999).
Financial or other inability as a defense is applicable in cases where the defendant can show: (a) An extrinsic factor caused noncompliance; (b) The accused had no control over the extrinsic factor; (c) Noncompliance was not due to the fault or design of the accused after he had an obligation to obey; and (d) The extrinsic factor could not be remedied by the accused’s timely, legal efforts.
United States v. Pinkston, 21 C.M.R. 22 (C.M.A. 1966). The Court found that the defendant was excused from obeying an order to procure new uniforms where the defendant was financially unable to, through no fault of his own.
United States v. Hilton, 39 M.J. 97 (C.M.A. 1994). In this case the Court disallowed a financial inability defense to dishonorable failure to pay a debt where the financial inability was a result of defendants own financial scheming.

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