A conversation with Clemens Hufeld (VP Legal Data at Noxtua and Lecturer at LMU) on mapping legal knowledge, new transparency in legal research, and new approaches to comparative law.

Interview: Dr. Clara Herdeanu, Chief Communications Officer Noxtua

We announced the Noxtua 5 product release just a few days ago. What exactly does it include, and what is so new about it?

For the first time, we are creating digital twins of entire legal systems. A digital twin is a dynamic model that encompasses not only documents but also the relationships between them. Knowledge graphs make these relationships visible and navigable.

With Noxtua, we can create digital twins of entire legal systems because, through our partnerships with leading legal publishers, we have built Europe's largest and most comprehensive legal database. Without all of this high-quality, curated legal data, we would not be able to do this.

For me, this is also a significant personal milestone: having studied both law and computational linguistics, I have been dreaming for years of applying knowledge graphs and digital twins to the legal sector. And now Noxtua is doing exactly that for the very first time.

What exactly is a digital twin in the legal sector? How can one picture it?

A digital twin is a representation of an object in the digital world. This already exists in various fields, such as the energy sector or the automotive industry. We are now applying this to the legal sector for the first time. A digital twin of a legal system is more than a database. It maps the structure, the relationships, and the evolution of law within a jurisdiction. It encompasses statutes, regulations, court decisions, commentaries — and crucially — the connections between them. After all, legal professionals do not work with isolated legal documents and information; we constantly relate the concepts discussed within them to one another. This act of connecting concepts is precisely what defines legal work — and with Noxtua 5, we are transferring that into Legal AI.

You also mentioned knowledge graphs. How do knowledge graphs differ from conventional AI-based legal research?

Conventional legal tech solutions are built on the search paradigm: you receive a list of documents sorted by keywords or semantic similarity. A knowledge graph, by contrast, is based on relationships within a network. Every document is a node, every relationship between documents an edge — much like the way legal professionals think: we navigate a multidimensional network, not a flat list.

Instead of searching for documents, legal professionals will be able to search by concept and ask, for example: "Show me all decisions that address the concept of "Verwirkung" in tenancy law." We are also developing this further so that in an advanced future form of these knowledge graphs, users will receive not only the decisions themselves, but also a visual representation of the doctrinal development of that concept over time.

Allow me a brief digression into linguistics here: this is somewhat analogous to the semiotic triangle from linguistics, which concerns the sign, the concrete object, and the concept in the minds of people. Translated into law, the statutory text is the sign, the regulated situation is the object, and the doctrinal concept is the mental model in the minds of legal experts. With Noxtua, we are now transferring this into the digital realm. We create digital twins of different legal systems and jurisdictions based on curated, high-quality legal data, with which lawyers can then generate dynamic knowledge graphs on demand — and, looking ahead, also work comparatively across legal systems.

By raising comparative law, you've introduced yet another topic. Why are digital twins and knowledge graphs important for comparative law?

Until now, lawyers have often compared only at the level of words — for example, "Treu und Glauben" versus "bonne foi." The knowledge graph enables comparison at the level of concepts. Lawyers can then literally see how legal concepts are actually connected, not merely how they are linguistically labeled.

How does this approach relate to classical legal methodology?

Classical legal methodology describes how lawyers solve problems — through interpretation, legal doctrine, and precedent. All of this is based on implicit knowledge. The knowledge graph makes this implicit knowledge explicit and visualizes the methodological pathways.

This all sounds like very exciting developments. But how exactly do users benefit from it?

The time factor is crucial. The knowledge graph enables an entirely new kind of research. Instead of spending hours searching through databases, lawyers can survey the relevant legal network or a line of case law development in seconds. This is particularly valuable for complex mandates that touch on multiple areas of law, or for questions such as where gaps exist in case law, which diverging lines of reasoning should be highlighted, and how doctrinal development has unfolded over time.

Your doctoral dissertation also engaged extensively with legal education. So let me ask: what impact could this have on legal training?

Students can learn not only individual provisions and decisions, but also visually grasp the connections between them. They see how doctrinal concepts develop and how the legal system functions as a whole. This creates the opportunity to gain systematic understanding visually, in seconds.

To summarize briefly and concisely: what is the potential of knowledge graphs and digital twins, and how can they improve the quality of legal work?

The quality of legal work depends significantly on how completely and precisely the relevant legal situation is captured. The knowledge graph reduces the risk of overlooking relevant material, makes visible connections that individual lawyers may not be aware of, and promotes transparency and consistency in legal decision-making.

And in the future, we will use it to make the connections between different European legal systems visible as well, which in turn fosters understanding of similarities and differences. This is especially valuable in an increasingly integrated European legal space.

Speaking of the future: how do you see the future of the legal profession in this light?

I envision a future in which legal professionals work within an interconnected ecosystem where the collective knowledge of European legal culture is navigable — an ecosystem in which we are not merely German, French, or Polish lawyers, but European legal professionals.

Thank you for your time!