In his fascinating article on law in Judaism, Joshua Berman divides post-talmudic halakhic authorities into roughly two schools: those who follow a codified or statutory-law approach and those who adopt a common-law approach. As against this, I would contend that everyone—even the codifiers—approaches the task of halakhic decision-making through a unique mix of common and statutory law. If the results sometimes convey an impression of arbitrariness or inconsistency, the fault lies in a misunderstanding of the system by which those results have been reached.
The Art of "Halakhah"
Why Jewish law is more a set of guidelines than of rules.