Does jurisdictional fragmentation cause sprawl?

We analyze jurisdictional fragmentation and sprawl utilizing municipal mergers as a quasi-experiment. We use Finnish population-wide register data with precise location information and compare the location of new buildings (and their residents) in the actual mergers to the location of new buildings in a control group of hypothetical mergers constructed from the pre-merger municipality map. We find that, in the smaller municipalities of a given merger new buildings were built about 10 per cent or 2 km closer to the new administrative center. These effects materialize after two municipal council terms (8 years) and are driven by mergers resembling functional urban areas.