Fragmentary, complex and in short supply, medieval Portuguese court records have been largely overlooked by historians, with the result that the judicial and intellectual workings as well as the social dynamics of legal practice in medieval Portugal remain, for the most part, unknown. Drawing on various examples from several cathedral archives in Portugal and interweaving them with royal legislation and ius commune sources, this article contends that, far from merely conveying a disparate array of impressionistic and disconnected glimpses into legal practice, these records are evidence of patterns of legal expertise that can be reconstructed and analysed. It focuses on three such patterns in particular: the exploitation of Romano-canonical procedural law and its flaws; the appeal to the papal curia; and the recourse to authoritative legal counsel abroad. These constants of legal practice not only shaped the experience of the law and litigants’ awareness of legal mechanisms in a fundamental way, but also sparked serious social tensions and provided a rationale for the attempts of Portuguese kings, from the 1280s onwards, to exert a tighter control over the legal process.