In Choate v. Trapp, 224 U.S. 665 (1912), the history of the Atoka Agreement was reviewed by the Supreme Court. It was there held that the provision for the exemption conferred, upon the allottees, property rights which were within the protection of the Fifth Amendment and hence it was not subject to repeal by later Congressional legislation; that the restriction, being one imposed in the exercise of the plenary power of Congress over the Indian tribes and tribal lands and in the performance of its duty as the guardian of its Indian wards, see Lone Wolf v. Hitchcock, 187 U.S. 553, 565 (1903), and having been accepted by the State of Oklahoma in its constitution upon admission to statehood, was a limitation upon the taxing power of the state. In Choate v. Trapp, 224 U.S. 665, 32 S.Ct. 565, 56 L.Ed. 941 (1912), the court, after noting the general rule that exemptions from taxation are to be strictly construed, said at page 675 of 224 U.S., 32 S.Ct. 565, 569: `But in the government's dealings with the Indians the rule is exactly the contrary. The construction, instead of being strict, is liberal; doubtful expressions, instead of being resolved in favor of the United States, are to be resolved in favor of a weak and defenseless people, who are wards of the nation, and dependent wholly upon its protection and good faith. This rule of construction has been recognized, without exception, for more than a hundred years, and has been applied in tax cases.'"