Arrest
You run your fingers along the words of a paragraph. You are learning about the law because you plan to arrest somebody.
Imagine reading the paragraph very slowly. You find your answer. It looks like you'll be able to arrest that person...
こう
かか
None
Who do you want to arrest? You want to arrest こういち. Even though he's started wars, created a religion, and trapped a child in a cavity, it's going to be tricky to arrest him because he's the emperor now.
Still, according to this paragraph you're running your fingers through, you can do it. You can arrest こういち.