¶1Charles Dorman was employed as mate upon a vessel described as a steam lighter named the “Herbert,” used by its owner in coastwise traffic for the transportation of sand and gravel between Scituate and Boston. At the time in question the “Herbert” was on a voyage over tidewater between these two places, and was in or just outside of Boston Harbor and within *584three miles of shore. Dorman was employed by the Boston Sand and Gravel Company, which was insured under the workmen’s compensation act, and which owned the vessel.
¶2It is assumed in favor of the dependent for the purposes of this decision that Dorman lost his life from causes arising out of and in the course of his employment. These causes manifestly were operative under such circumstances as to bring any legal liability arising therefrom within admiralty cognizance. The locality of the incident is decisive upon that point. “Every species of tort, however occurring, and whether on board a vessel or not, if upon the high seas or navigable waters, is of admiralty cognizance.” The Plymouth, 3 Wall. 20, 36. Proctor v. Dillon, 235 Mass. 538, 541.
¶3The circumstance that the "Herbert” was engaged exclusively in commerce within the territorial limits of this Commonwealth and did not go outside the three mile limit does not divest the occurrence of its admiralty character, which depends wholly upon the question whether it is upon navigable waters. The Robert W. Parsons, 191 U. S. 17. See North Pacific Steamship Co. v. Hall Brothers Marine Railway & Shipbuilding Co. 249 U. S. 119; Atlantic Transport Co. v. Imbrovek, 234 U. S. 52.
¶4The workmen’s compensation act is broad enough in its terms to include cases like the one at bar. But it is plain from the facts here disclosed that that act (apart from a federal statute to be mentioned in a moment) could not be operative in favor of the dependent under the Constitution of the United States. That was settled beyond question by Southern Pacific Co. v. Jensen, 244 U. S. 205, decided in May, 1917. We were constrained to follow that decision in Duart v. Simmons, 231 Mass. 313; S. C. 236 Mass. 225, and in Sterling’s Case, 233 Mass. 485. After the decision in the Jensen case Congress attempted to confer jurisdiction upon the several States to deal with cases like the present by workmen’s compensation laws by the enactment of 40 U. S. Sts. at Large, 395, § 2, approved October 6, 1917. Seemingly the exclusive nature of federal jurisdiction under admiralty law was released to the States by that act taken at its face value. Duart v. Simmons, 231 Mass. 313, 320. The constitutionality of that act was assailed, however, and by the decision in Knickerbocker Ice Co. v. Stewart, 253 U. S. 149, rendered since this case was heard and decided by *585the Industrial Accident Board, it was held to be invalid because beyond the powers of Congress under the Constitution. We are bound by that decision. It is decisive against the right of the dependent to compensation in the case at bar. See also Sudden & Christenson v. Industrial Accident Commission, 182 Cal.
¶5There are no circumstances disclosed on this record which estop the insurer from availing itself of this point, or which show a waiver of its right to this defence. That is settled by Sterling’s Case, supra. The point goes to the jurisdiction of the court, which cannot be established by considerations arising from conduct of parties. The case is quite distinguishable from cases like Pitkin v. Springfield, 112 Mass. 509, and Hellen v. Medford, 188 Mass. 42. By force of the controlling authority of Knickerbocker Ice Co. v. Stewart, 253 U. S. 149, the entry must be
¶6 Decree reversed.
¶7 Decree to be entered in favor of the insurer.