As for the use case, it seems to be an explorative exercise to see if something like that can help provide more transparency and consistency within systems of law, "whether machine-executable legislation can provide an answer" to complex and opaque cases. The websites linked earlier have more information + examples.

Bringing the boring old legal system closer to smart contracts.

But I don't have a clue if this is really the case.

I think that's the project.

"Modern calculation engine as a building block for the entire government. In collaboration with the Benefits Service (Dienst Toeslagen). Can we develop a general calculation engine for the government? This project explores how such a system could help in executing complex regulations for citizens and businesses, for example, when calculating benefits."