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    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>A Toolset for Normative Interpretations in FLINT</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Anna van Buerenplein</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>The Hague</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>The Netherlands</string-name>
        </contrib>
      </contrib-group>
      <abstract>
        <p>In light of the challenges in tracking and comprehending diverse interpretations of legal texts, this paper introduces a method for norm interpretation using ontologies and digital tools. We propose the FLINT ontology, a language for expressing interpretations of normative sources, as well as a set of software tools to support its utilization. The FLINT ontology represents norms as normative acts with pre- and postconditions. Each of these elements are linked to its source, ensuring traceability and explainability. The software tools we introduce in this paper include a source decomposition application that converts normative documents into RDF-based representations, a norm editor for creating interpretations of norms based on FLINT, and the integration of an automated assistance module that generates annotation suggestions to assist users in encoding normative texts.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Norms</kwd>
        <kwd>Normative systems</kwd>
        <kwd>Legal interpretation</kwd>
        <kwd>FLINT</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>Norms can be subjected to multiple interpretations. Not having a reference model allowing to
indicate which interpretation has been applied to a given normative source, such as a legal text
or regulation, makes it challenging to track from which perspective it has been interpreted. This
issue becomes even more problematic when trying to keep track of decision-making processes,
as the interpretation of rules directly influences the outcomes.</p>
      <p>Ontologies can help to record information regarding the interpretation of norms. When
they are integrated within digital tools, they facilitate normative cooperation and foster further
reflection on how a certain regulation has been interpreted by diferent users. Moreover, they
may allow stakeholders to reach deeper insights into the underlying logic of norms, leading
them to further discuss on the interpretation that should be applied to norms.</p>
      <p>
        To enable eficient tracking of the interpretation that has been employed to structure data
of rules and regulations, we worked on solutions fostering the representation of normative
knowledge based on a sound theoretical foundation. As part of this endeavour, we developed
an ontology for the FLINT language [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. Complementing this ontology, we have designed
a comprehensive set of tools to support its utilization. They allow to A) create semantic
representations of the structure of law documents, to relate interpretations back to their source,
B) create interpretations of law documents by tagging and structuring data based on the
expressiveness of the FLINT ontology, and C) generate suggestions for the ontological categories
under which pieces of textual information regarding norms shall be structured.
      </p>
      <p>The rest of the paper is set up as follows. We start by giving a brief overview of the state
of the art of normative ontologies and the tooling that is available to utilize them in Section 2.
We then introduce the FLINT ontology in Section 3 and describe the tooling in Section 4. We
conclude in Section 5.</p>
    </sec>
    <sec id="sec-2">
      <title>2. State of the art</title>
      <p>
        Numerous vocabularies and ontologies have been developed to structure and organize data
relating to norms [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. We focus on representing the full normative action space available to
agents across all relevant contexts. Therefore, our work is at some distance from solutions
focusing on obligations and prohibitions or evaluating violations of situations rather than
actions, such as LKIF [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], LegalRuleML [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] and recent work by Francesconi &amp; Governatori [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ].
      </p>
      <p>
        Arguably the most relevant comparison for our work is to the UFO-L Legal Core Ontology
[
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. UFO-L provides a formal description of legal relations. Similar to FLINT, UFO-L has a
rich representation for classes of power—liability relations, including ways of identifying what
classes of actors can occupy which legal positions within the relation (power holder, liability
holder). As far as we are aware, no tooling exists to generate interpretations of normative
sources in UFO-L, or any of the other ontologies mentioned above.
      </p>
      <p>
        A line of work focused on mapping normative texts to formal models by means of an
annotation tool is that of Dynamic Condition Response (DCR, [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]). This framework allows to
map textual segments of norms to DCR graphs. Its primary aim is to enable mapping between
law texts and code executing the law. By doing so, it enhances transparency on decision rules
that are written in a procedural programming language. The editor however does not allow
to structure data against the expressiveness of RDF-based ontologies, nor is it intended to do
so. A similar initiative, focused specifically on obligations in contracts, extracts knowledge
from natural language contracts in the form of Obligation Logic Graphs, and in turn maps these
graphs to executable code [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. Due to space constraints, a thorough comparative analysis of the
aforementioned related works will be reserved for a future publication.
      </p>
    </sec>
    <sec id="sec-3">
      <title>3. FLINT ontology</title>
      <p>FLINT is a language that can be used to express interpretations of normative sources, while
also serving as a basis for technical implementation. It does so by representing norms in terms
of normative acts and their pre- and postconditions. The FLINT ontology is developed in
RDF/OWL and is publicly available under an open-source license.1</p>
      <p>
        FLINT’s central concept is the frame: a container that bundles several pieces of information
[
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. At the highest level, we distinguish two types of frames. Fact frames describe matters
that characterize the state of the normative system. Act frames describe actions that agents
might take, which afect the state. An act frame is connected to fact frames that describe
1The repository can be found at https://gitlab.com/normativesystems/knowledge-modeling/flint-ontology. For
documentation, see https://normativesystems.gitlab.io/knowledge-modeling/documentation-website/docs/.
who can perform the act, who can undergo the act and what objects can be afected by it. Its
preconditions describe the circumstances in which the act can be performed legally, while its
postconditions are given in terms of the facts that become true and false by means of the act.
      </p>
      <p>An important characteristic of FLINT, which is reflected in our ontology, is that each frame
contains a reference to the source that this frame is an interpretation of (e.g. one specific
sentence in a law text). These references ensure that the interpretation is explainable and
traceable. To support fine-grained referencing, we developed a source ontology module that
describes the structure and content of a source of norms.</p>
    </sec>
    <sec id="sec-4">
      <title>4. Tooling</title>
      <p>The software modules that we designed aim to support data-structuring activities related to
norms while providing the possibility to everyone to specify and inspect information regarding
rules and regulations. The target users for our tooling are legal experts, public administrators,
non-profit organizations, businesses, and citizens. In fact, we envision a world where anyone
can contribute to the clarification of the normative systems they participate in.</p>
      <p>The tools are meant to exchange data in a standardized way, following the previously
mentioned ontology modules. This ensures that the tools can also be used independently and in
combination with other software. We describe the tools in detail in the following subsections.</p>
      <sec id="sec-4-1">
        <title>4.1. Source Decomposition</title>
        <p>The first module of our tooling is an application for preparing any source of norms into a format
that allows fine-grained referencing. This application, which we named Choppr, converts a
document into an RDF-based representation of the structure and contents of that document.2
The process is semi-automatic: our source decomposition tool takes as input any text file, and
allows the user to develop and test a set of instructions for the decomposition of the document.
The instructions are based on scoped, sequential application of regular expressions. The tool
can export the decomposition result as RDF-compliant data, using the concepts of the source
ontology module.</p>
      </sec>
      <sec id="sec-4-2">
        <title>4.2. Norm Editor</title>
        <p>The second module of our tooling is the norm editor.3 It is an application, built using web-based
technologies, which allows a user to create interpretations of sources of norms in FLINT in a
user-friendly and interactive way. The code of the editor is open source.4</p>
        <p>The editor consists of three main panes. In the source view pane, a decomposed source as it is
generated by the Choppr tool can be imported. The decomposed source is rendered and allows
the user to annotate pieces of textual information according to the expressiveness of the FLINT
ontology (acts, facts and their subtypes). It provides the capability to continuously observe the
relationship between each FLINT frame and the corresponding source of the regulation. In the
2A prototype, developed in collaboration with software company Tick, is available at https://choppr.app/.
3A prototype of the norm editor can be accessed at https://norm-editor.tnodatalab.nl/.
4The repository can be accessed at https://gitlab.com/normativesystems/ui/interpretation-editor.
interpretation actions pane, an overview of the already annotated parts is given. Additionally, the
user can select an annotation and include it in the supported interpretations actions (creation
of facts and acts) of the right pane. The final step, exporting the interpretation in RDF, is under
development.</p>
      </sec>
      <sec id="sec-4-3">
        <title>4.3. Automated Assistance</title>
        <p>
          In the process of encoding textual information into the FLINT ontology, users are supported
by automated suggestions. For this we use a software module that can automatically generate
tag suggestions for stakeholders, developed by Bakker et al. [
          <xref ref-type="bibr" rid="ref10 ref11">10, 11</xref>
          ]. This module uses a
transformer-based model, fine-tuned on annotated law texts. It adds semantic role labels to
parts of sentences in source texts, which map to FLINT concepts (actor, recipient, action, object).
By incorporating this module into the editor, we enable users to utilize these suggestions, to
save time during the manual encoding of normative texts. As AI capabilities improve, the tool
can assist users in spotting human errors and guarantee comprehensiveness of annotations by
suggesting tags for text segments that the stakeholders might have overlooked.
        </p>
      </sec>
      <sec id="sec-4-4">
        <title>4.4. Software Ecosystem</title>
        <p>The information exchanged between the components of our software tooling follows the path
that users undertake to structure normative textual information. These steps include
decomposing a source, manually or automatically encoding the segmented texts into the expressiveness
of the FLINT ontology, and saving FLINT encoded information into the repository of choice. By
following this process, the generation of structured data regarding norms becomes a streamlined
process, allowing for easy sharing and dissemination of information. It ultimately supports
the creation of machine-understandable data that can feed diferent sectoral ecosystems while
contributing to interoperability of information.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>5. Conclusion</title>
      <p>In this paper, we reported on our developments of tooling for legal interpretation. We presented
OWL ontologies formalizing relevant concepts, including a language to describe normative
systems, and a representation of the content and structure of normative sources. We presented
software tooling to support decomposition of normative sources, and manual and
computerassisted interpretation of those sources.</p>
      <p>The tooling presented in this paper is still in active development. Usability tests are planned
in the fall of 2023. Although FLINT has been tested in case studies, we have so far worked with
manually created models without the use of tooling. We are now working on case studies to
also test the maturity of the tools. For example, we are creating an interpretation of the Dutch
budget laws in order to see whether we can accurately model the national budget cycle.</p>
      <p>In addition, we are pursuing computational implementations of FLINT interpretations in
order to automate normative reasoning. A norm engine based on the FLINT ontology is under
development, which uses the ontology in combination with SHACL constraints and inference
rules to reason about the lawfulness of acts in concrete scenarios.</p>
      <p>As part of our future work, we intend to conduct a comprehensive comparison with the other
normative ontologies and tooling mentioned in this paper, aiming to gain valuable insights into
their similarities, diferences, and overall eficacy.</p>
    </sec>
    <sec id="sec-6">
      <title>Acknowledgments</title>
      <p>We thank the Dutch Ministry of the Interior and Kingdom Relations for financially supporting
our research. We are also grateful to Kamiel Naaktgeboren and Tinus Koorn for the development
of Choppr and to Rutger Dik and Robert van Doesburg for their work on Choppr and the norm
editor.</p>
    </sec>
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