The German government apologized for attacking "Gulflight", but refused to change its strategy of unrestricted submarine warfare. A report by the British admiralty into the attack concluded that the German commander had behaved properly according to "Cruiser rules" defined in international law. A merchant ship under escort by military vessels forfeited any right to be warned before being attacked, so the patrol ships had made "Gulflight" a legitimate target by taking her under escort. As an American ship, the submarine would not have attacked had he seen her nationality, but apart from an ordinary flag "Gulflight" was not carrying any additional markings painted on the hull to make clear her nationality, which other ships were then doing. The report also suggested that the tanker being stopped and then slowed down by the accompanying patrol had made her an accessible target. The Admiralty report was not published at the time and official comment did not explain the circumstances.