1- Sources of Roman Law:
The sources of Roman law form the basis of contemporary continental European law. We examine this period in three sections: pre-Justinian sources, Justinian’s compilation (Corpus Iuris Civilis), and post-Justinian sources.
A- Pre-Justinian Sources of Knowledge: The most important source of knowledge prior to Justinian is the book Institutiones (institutions), prepared by Gaius and consisting of four sections. This book covers the fundamental institutions and concepts of law.
B- Justinian’s Compilation of Law (Corpus Juris Civilis): Justinian ordered jurists to undertake codification work in order to consolidate and enact the law. As a result of the jurists’ compilations, the four-part Corpus Juris Civilis compilation was prepared, including Justinian’s edicts.
The first section of the collection is Gaius’ book Institutiones.
Th e second section is the Digesta (Pandecta). The most comprehensive and extensive section is the Digesta. Th Digesta is a section compiled from the works of classical period jurists, organized according to a specific system, classified, and published. The Digesta contains texts describing concrete cases. Abstract rules were derived from these concrete cases.
The third section is the Codex, which consists of imperial edicts.
The fourth section is the Novellae. This section is similar to the Codex, but consists solely of the edicts of Emperor Justinian.
However, in the examples of the Corpus Juris Civilis available today, there is a fifth section consisting of the Interpolatio and Glosses. Classical jurists were consulted during the preparation of the Corpus Juris Civilis. The changes made to adapt them to the period are called Interpolatio. These are actually intentional changes. Glossas, on the other hand, are notes written on the original text to aid in legal education and are considered part of the original text and evaluated as a change.
C- Post-Justinian Sources of Information: Post-Justinian sources of information are sources from the Byzantine period. Examples include the Basilica, which consists of royal laws expressing the products of Byzantine law, and the Hexabiblos, a compilation by a Thessalonian judge.