In the case of In re Grimley, the petitioner was a soldier who had enlisted in the army but later sought to be discharged on grounds that he did not fully understand what he was signing up for due to his limited understanding of English. The Supreme Court ruled against him, stating that ignorance is not an excuse and it's one's responsibility to ensure they comprehend any agreement before entering into it. The court held that even if there were misrepresentations made by recruiting officers or others about terms of service, these would not invalidate enlistment contracts as long as no fraud occurred. This ruling established a precedent regarding military enlistments and contractual obligations more broadly.

The dissenting opinion in the case of In re Grimley, 1890, argued that the military court had jurisdiction over Grimley's case and thus his habeas corpus petition should be denied. The justice contended that as a soldier who enlisted voluntarily, Grimley was subject to military law and its penalties for desertion. He further asserted that civilian courts should not interfere with military matters unless there is clear evidence of abuse or lack of due process. This view held that the majority’s decision undermined the authority and effectiveness of military discipline by allowing soldiers to escape punishment through civilian courts.