# Solon: A Holistic Approach for Modelling, Managing and Mining Legal Sources
## 1 Introduction  
Public legal information, a part of the common heritage of humanity [1], is a large collection of different normative documents, which keeps growing and changing with time. Nowadays, as a consequence of initiatives for open data and especially open government data, there is a huge increase in the number of portals providing legal documents to interested parties. Legal sources, to which only a qualified audience had access, are now freely available. Although this open access is usually supported by services such as thematic navigation and keyword search, legal sources are primarily stored and disseminated in a semantically poor text representation that does not reflect the structure and semantics of legal data. Legal sources availability in a structured and standard format, the existence of a common reference vocabulary between the systems involved, is a necessary prerequisite for effective legal document dissemination. Towards this end, national and international initiatives have proposed standards for the semantic representation of legal sources [2; 3; 4]. However, as the World e-Parliament survey 2016 [5] reports only 26% of parliaments distribute documents in XML format and 49% operate document management systems. Legal data is mainly offered to the end user in a friendly and human readable manifestation, primary presentation oriented e.g., PDF. In this paper, following functional requirementsfor bibliographic records (FRBR) terminology [6], we do consider a manifestation to be the physical embodiment of an expression of a work, any different realisation of an expression i.e., paper format, digital format, etc. The use of such proprietary and unstructured format, makes it impossible to establish an interoperability layer among the different sources of information, to allow reuse and interconnection with repositories in the Semantic Web, overall hampering opportunities for openness and transparency. At the same time, the recent abundance of Open Legal Data poses extra overhead for both citizens and legal professionals to find useful and relevant legal sources. Consider, for example, a compliance manager researching whether a given company is conducting its business in full compliance with national, and potentially international, laws and regulations specific to a particular industry. He/she has to iteratively browse an enormous number of legal documents, obtained iteratively through keyword queries, most probably in PDF format, selecting, through knowledge and experience, relative documents in order to comprehend conditions and grounds. A legal information system providing refined search results, semantically represented, interlinked and enhanced with classification features is intuitively more informative and helpful that a set of relevant PDF files. Furthermore, as the legal doctrine increases in volume and complexity, finding a relevant norm may be a challenging task even for experts. To alleviate the data overload problem, modern legal information systems are not only intended to provide advanced search tools for users, but also to organize the legal order, to monitor the impact of the new rules on the regulation, to manage documents life-cycle and different versions chronology [7]. In this paper, we present Solon, a legal document management platform. [PERSON] was an Athenian lawmaker remembered particularly for his efforts to legislate against political, economic, and moral decline in archic Athens. He is credited with having laid the foundations for Athenian democracy. Solon's main goal is to assist users reference and retrieve legal and regulatory documents within the exact context of a conceptual reference. It consists of several different components, exposed as Representational State Transfer (REST) services. It is an advanced legal document management platform, operating on legal sources that are automatically discovered and collected from authoritative portals with the help of Web Harvesters/Crawlers on a scheduled basis.