The way Emperor Justinian adapted Roman law for use by the Byzantines:
The Corpus Juris Civilis, also known as Justinian Code in Renaissance, was commissioned by Justinian.
The Corpus Juris Civilis had four parts:
The research aimed at reorganizing the judicial system of the Empire that has become dysfunctional over time, at opposing obsolete laws and those that have been abolished, and at changing the ambiguous passages.
At its release in 529, the first was redundant because it covered acts already redundant and it didn't contain acts published in the meanwhile. This version has already been destroyed. The second book was published in 534.