Mishnaic halakhah is presented in various forms such as precedents, enactments, edicts, customs, and, most commonly, casuistic formulations (i.e. case law). General rules also appear in the Mishnah, but they are the exception as mishnaic halakhot are usually embedded in specific cases and circumstances. Since the rationales underlying the halakhot of the Mishnah are rarely stated explicitly, scholars analyse halakhot so as to expose their implicit legal basis. At times, the implied legal reasoning for a halakhah may be ad hoc and cover little more than the specific case cited, while at other times, the implicit reasoning may involve a general principle with broader application.
Amram Tropper, “The State of Mishnah Studies,” Rabbinic Texts and the History of Late-Roman Palestine, ed. Martin Goodman & Philip Alexander (Oxford: Oxford University Press, 2010), 100.