Wiktionary
vb. (context legal transitive English) To make a decision in an official capacity regarding some matter.
Usage examples of "rule on".
That Darken Rahl knew which box would kill him was troublesome, but he reasoned that Rahl might be using the Wizard's First Rule on him.
Darken Rahl is using the Wizard's First Rule on me, trying to turn us against one another.
You are among those who rule on this world while Sardia is only a woman who acted unwisely while under the influence of wine.
He, who has based his rule on repression and fear, is resolute in not surrendering even though he has already suffered a critical defeat.
Both groups had gone to enforce their rule on those who had traveled to live in the New World, and on those who had always lived there.
But by that day the church must be able to impose once again its rule on the conflict.
In other words, what happens or follows must follow according to a general rule on that which was contained in a previous state.