The S.S. Lotus (France v. Turkey) case is one of the landmark judgments in international law, concerning the State sovereignty and the exercise of criminal jurisdiction. The dispute arose after a collision on the high seas between the French vessel Lotus and the Turkish vessel Boz-Kourt on 2 August 1926. The collision caused the Boz-Kourtto sink and resulted in the deaths of eight Turkish nationals. After the Lotus reached Constantinople, Turkish authorities initiated criminal proceedings against Lieutenant Demons, the French officer who had been on watch at the time of the collision. France objected and argued that only the flag State could exercise jurisdiction. The dispute was later submitted to the Permanent Court of International Justice (PCIJ). On 7 September 1927, the Court, by the President’s casting vote, held that Turkey had not acted contrary to international law by prosecuting Demons. The Court’s central reasoning was that the effects of the collision occurred on a Turkish vessel and that Turkey was not prohibited by any rule of international law from exercising jurisdiction. The Court also refused to presume restrictions upon the independence of States. This judgment became associated with the Lotus Principle and influenced the proposition that restrictions upon the independence of States must be established by international law. Although the case remains significant, its approach to criminal jurisdiction over high-seas collisions was subsequently limited by treaty law. Article 11 of the 1958 Convention on the High Seas and Article 97(1) of the United Nations Convention on the Law of the Sea (UNCLOS) introduced specific rules governing penal or disciplinary jurisdiction arising from collisions and other incidents of navigation on the high seas. This case commentary examines the differing opinions, subsequent treaty developments, the Court’s reasoning, and assesses whether the Lotus Principle continues to influence questions of jurisdiction under international law.