This research aims to analyze the arguments of legitimization that were used in the reform of Brazilian procedural legal codes, by comparing the texts of the statement of reasons of the Civil Procedure Code of 1939 and the draft bill of the New Civil Procedure Code. We consider these codes as milestones: the Civil Procedure Code of 1939 was the first one with a national scope; the draft bill of the New Civil Procedure Code was the first one produced during a democratic period. Our goal is to search for similarities and contrasts between the legitimization arguments used in each historical and political period, by asking if they were only arguments to bestow legitimacy to such reforms. We decided to use the methodological tools of sociolinguistic analysis of speech developed by Patrick Charaudeau in his analyses of political speech in order to elucidate how the uses of language and elements of meaning in the speech construction provide justification for the concept of procedure, in both 1939 and 2010. As a result, we conclude that the process of drafting the CPC of 1939 and the New CPC, even if they are very distant in terms of political and historical contexts, they are also very close in their rhetorical construction and their attempt to find justification and adherence. On balance, some of the differences depend on the vocabulary used when the codes were developed, their justification and the need for change.