Tests for correctness, self similarity, duplication of concerns, contradictory statutes, edge case detection, cruft or outdated laws that muddy the waters...
If the full compliment of software development practices were applied to legislation and ordinances we would be living in a very different world.
Jurisdictional laws don't work that way though. It's more like a script for improvised theater. Everybody get the same text, but no one gets the same performance twice.