2 Context
2.1 The Importance of Text Identification in Legislation
In HTML, the primary link type is anchor-to-document , while anchor-to-anchor links are a minor addition for uncharacteristic cases. For this reason identifiers are never required: authors are expected to provide identifiers only for those structures that are likely destinations of anchor-to-anchor links – often just a few section headings.
In legislation, on the other hand, ALL references are to a precise substructure of a highly hierarchical document flow, and any substructure may become a destination. This is the reason why identifiers are useful for most structures of a legislative document.
Additionally, in HTML the reference is usually meant for navigation by human users. It is only necessary to come close enough to the intended destination that a human eye can scan the surrounding text or elements and find the exact destination in the vicinity.
In legislation, there is an additional type of reference, “modification”. Modifications require that a specific substructure be precisely identified and modified by a modification instruction. In this case, one cannot be satisfied with the fact that the intended destination is somewhat near the arrived destination -- they must coincide.
By using the layering provided by the Functional Requirements for Bibliographic Records (FRBR) (See Section 4.1), Akoma Ntoso strongly differentiates between the legislative context and the markup used to represent it. References are legislative concepts, and exist regardless of whether they exist in the markup. The same content, for instance, could be represented in a number of different XML files created by various authors. They would all be distinct manifestations of the same Expression, each of which may have the same body, but different markup choices, metadata, commentary, etc. References would need to work regardless of the specific Manifestation chosen as the destination, and, indeed, it is important that all manifestations use the same identifiers for the same structures, standardized by the LegalDocML Technical Committee. This is affected by the fact that an author may not even have the document of the destination, or that it may not even exist yet (time-based alchemies frequently occur in legislation, one might need to create links to documents that have yet to be converted into Akoma Ntoso, etc.). Thus, providing a forced and precise syntax for identifiers is the best guarantee that all different manifestations of the same content have the same identifiers and that one does not need to read an XML file to divine the values of its identifiers.
Legal references have peculiar traits regarding time. For instance, in the case of an evolving document (e.g., a piece of legislation receiving references and being actively modified by the legislator), the actual destination of the reference is neither the original version, nor the current version, but in many cases the version of the document that was valid at the moment in time when the case took place. References are dynamic rather than static, because the destination moves in time and jurisdiction according to the needs rather than being fixed to a specific sentence or fragment. This means that point-in-time consolidation is an important affair, and that determining the destination of a dynamic link requires, at the very least, that structures existing in multiple versions are named consistently. For example, it must be clear that, if section 35 of the initial version of a title of a U.S. code had some identifier y , then ALL subsequent versions of that same section 35 (even after a renumbering action) have the same identifier y , so that once you determine the needed version, arriving at the right structure is easy and straightforward.
The syntax of identifiers is defined to ensure that identifiers can be used regardless of the versions of the same document, regardless of the author of individual XML markups, regardless of usage of navigational or modification references, and knowing full well that point-to-point references are the norm rather than the exception.
The Akoma Ntoso naming convention does not assume that the document is stored in Akoma Ntoso XML, but only that there is a mapping between the FRBR IRI reference and the URL of a file stored somewhere on the Internet, and to which our reference can be resolved into.
In the case of identifiers, the Akoma Ntoso naming convention does not assume, yet again, that the document is stored in Akoma Ntoso XML, but only that identifiers work in whatever format has been used. This means that any XML-based language, including Akoma Ntoso, HTML, TEI, DocBook, ePub, kf8, or Mobi are acceptable and can make use of the Naming Convention presented here.
The Akoma Ntoso Naming convention also assumes that it is the job of the author of the linked-to document to use identifiers that are consistent with the naming convention. This is necessary because, in HTTP, the fragment identifier is never sent with the request and is only known and handled by the user agent, so we must assume that identifiers are present in the response and have the correct form. In particular, it would make no sense to convert all fragment identifiers in references using the syntax of the destination documents, as these syntaxes can be quite innumerable.
Identifiers are the main way Akoma Ntoso identifies fragments and parts of the document in an unambiguous form. They can be used in document references (e.g., links and amendment commands) as a precise pointer to the actual part of the document mentioned (as opposed to simply referring to a document as a whole).
Identifiers are systematically used in Akoma Ntoso. All Akoma Ntoso elements allow up to three identifiers. Even internal links need to use identifiers. Most relevant elements and sections require at least one identifier.