This section is from the book "The Law Of Real Property and Other Interests In Land", by Herbert Thorn Dike Tiffany. Also available from Amazon: A Treatise on the Modern Law of Real Property and Other Interests in Land .
While the Rule in Shelley's Case takes its name from a case of that name which turned upon the application of the rule,36 the rule itself appears to have been recognized at a much earlier date.37 We have no evidence as to the considerations upon which the earlier assertions of the rule by the courts were based, and the original purpose of the rule has been a frequent subject of conjecture. The theory in this regard which appears to be most generally approved is that the rule was originally based upon a desire to secure to the lord the feudal perquisites to which he was entitled upon the descent of the land at the tenant's death, the burden of which would have been to a great extent avoided if it had been possible, by a limitation to the heirs of the tenant as purchasers, to enable his heir to secure the same benefit as he would have obtained by descent, without the burdens incident to the latter mode of acquisition.38 It has also been suggested that its purpose was to prevent the inheritance from being in abeyance, a result which the courts always sought to avoid,39 and that it was based on a de34. See ante Sec. 26.
35. Fearne. Cont. Rem. 178: Whiting v. Wilkins, 1 Bulstr. 219; Evans v. Evans, (1892) 2 Ch. 173; Grant v. Squire, 2 Ont. L. Rep. 131; Reutter v. McCall, 192 Pa. 77, 43 Atl. 398.
36. 1 Coke 93. Shelley's case is discussed at length by Mr. Challis, and is shown by him to have involved a direct adjudication in favor of the rule, in spite of occasional statements to the contrary. See Challis, Real Property, C. 13.
37. Abel's Case, Y. B. 18 Edw. 2, 577 (anno. 1324); Provost of Beverley's Case, Y. B. 40 Edw. 3, 9 (anno. 1366) appear to have recognized the existence of the rule. See Williams, Real Prop. (21st Ed.) 346.
38. Hayes, Limitations, 52; Challis, Real Prop. 161; 1 Preston, Estates, 295; Fearne, Cont. Rem. 83 et seq.
39. Justice Blackstone in Per-rin v. Blake, Hargrave's Law Tracts, 498.
[Sec. 150 sire to facilitate the alienation of land by vesting the inheritance in the ancestor.40 As a logical justification of the rule reference has also been made to the consideration that in a jurisdiction where, as in England, primogeniture exists,41 the word "heirs" cannot usually refer to a definite group of co-existing persons, and must refer to an indefinite number of persons to take in succession, a succession which can be effected only by descent, to be traced from the ancestor named.42 These and various other reasons assigned for the existence of the rule,43 involve, however, the assumption that the limitation by way of remainder to the heirs or heirs of the body is valid as such, but it is to be borne in mind that, at the time when the rule was first recognized, at least as early as the fourteenth century, such a remainder in favor of unascertained persons, was invalid.44 Consequently it was impossible for the heirs to take as purchasers, and the only way of giving effect to the donor's intention that heirs should have the land after the death of the ancestor was by giving the latter an estate of inheritance.45 Thus regarded, the effect of the rule was to give to the limitation in favor of heirs an effectiveness of which it would otherwise have been entirely devoid.