LegalHTML: Semantic mark-up of legal acts using web technologies

We introduce here LegalHTML, an extension of the HTML language thought for representing legal acts. LegalHTML has been conceived in the context of an exploratory study conducted for the Publications Office of the European Union, with the objective of overcoming the proliferation of formats for the electronic redaction of legal acts, dedicated to different steps of the editorial process (e.g. first draft, content editing, proof reading, introducing semantics, publishing) and of realizing a model and a language that could bind all processes and exigencies under a common umbrella. LegalHTML satisfies these requirements by providing an explicit domain language addressing all structural aspects of an act, such as articles, paragraphs, items, references and an associated ontology (foreseeing both inline annotations through RDFa and explicit RDF code within script elements) providing rich semantics to describe the editorial and jurisdictional history of the act and to insert references to entities of the domain. Being based on HTML, presentation is also offered by the same language, an aspect missing from all most notable standards for the legal domain. Furthermore, LegalHTML addresses consolidation of an act and its subsequent modifications into a single document using a tree-based representation of the original content and of its modified versions. Finally, alongside the language & ontology, we implemented a CSS stylesheet for the default rendering of LegalHTML documents and a JavaScript file imbuing documents with an API supporting TOC generation, footnote cross-references and the said point-in-time visualization of consolidated legal acts.