In the case of Jackson v. Lykes Bros. Steamship Co., Inc., 1966, the U.S Supreme Court was asked to determine whether a seaman could recover damages for injuries sustained while working on a ship that was docked in port but not attached to shore. The plaintiff, Jackson, had been injured when he fell from a ladder while painting the side of his employer's (Lykes Bros.) ship which was anchored in navigable waters off Louisiana coast and sought compensation under Jones Act - federal legislation providing rights to sailors who are injured at sea due their employer’s negligence. The court ruled in favor of Jackson stating that even though the vessel wasn't moving or attached to shore during time of injury, it still constituted as being "in navigation" because it hadn’t been taken out of service or dry-docked; hence making him eligible for protection under Jones Act. This decision expanded interpretation regarding what constitutes “at sea” and broadened protections available for maritime workers.

The dissenting opinion in the case of Jackson v. Lykes Bros. Steamship Co., Inc., argued that the majority's decision to allow a seaman to recover damages for injuries sustained while ashore on leave was inconsistent with previous court rulings and maritime law principles. The dissent contended that, traditionally, a shipowner's duty towards its crew does not extend beyond the ship itself or activities directly related to service aboard it. They further pointed out that there is no legal precedent for holding an employer liable for an employee’s actions during their free time off work unless those actions are somehow connected to their employment duties - which was not proven in this case according to them. Therefore, they believed that extending liability as such would create undue burdens on shipping companies and potentially disrupt maritime commerce.