Comparison definition. Under Massachusetts law, the determination of whether the contract or tort statute of limitations applies is controlled by the essential nature of a party's claim. See Hendrickson v. Sears, 365 Mass. 83, 85 (1974); Kagan v. Levenson, 334 Mass. 100, 103 (1956). See also Desmond v. Moffie, 375 F.2d 742, 743-744 (1st Cir. 1967).