Let's take as given that the essence of the judicial power, the core of the judicial power, is the power and responsibility to decide cases within the court's jurisdiction in accordance with governing law. Well, to do that, a court deciding a case has to figure out what the governing law is. It has to ascertain the sources of law, figure out what those sources say. And there are lots of sources of things that can plausibly be called law. Constitution is a plausible source of law. Legislation, plausible source of law. Common law norms, a plausible source of law. Past judicial decisions might be a plausible source of law. Administrative regulations. There are lots of different things that you can look out there, identify, and plausibly attach the label "law" onto. So imagine that you're a court and you're trying to decide a case. You look out at all of these different sources. You gather them up. There's law number one and law number two, law number three, law number four. All these different sources, all of them come claiming to be law. It turns out that they don't all point in the same direction. If they do, if they all point in the same direction, this is gonna be an easy case. What if law one and law two sources say X, and law three and law four sources Y, or non-X? What do you do then? Well, this is a very common kind of occurrence any time there's more than one source that can plausibly claim to be a source of law, and there's an entire body of doctrine, an entire law school course called "Conflict of Laws" and all that that deals with is, what do you do when different sources of law come into conflict? Which one prevails? You could have a situation where the law of Maine conflicts with the law of Nebraska, and the case is being heard by a court in Texas and it has to decide which state's law is going to govern. It could happen when a case is heard in the United States and one of the parties claims it's governed by the law of Norway. Another party claims it's governed by the law of the United States. Well, court has to decide which is the body of law that's going to govern. And sometimes when those sources come into conflict, you have to make a hierarchy. You have to decide which one prevails over another. You've got a statute that says X. You've got an administrative regulation pursuant to that statute, that says Y. Can the administrative regulation beat the statute? Well, your intuitive answer I think is, "No. The statute is higher on the rung of supremacy than the administrative regulation." And that's correct. And one of the things a court in that kind of case would have to decide is, "Okay, I've got the statute. I've got the administrative regulation. They point in different directions. The statute wins." Now suppose a court gets a case, somebody comes in claiming there's a statute that says that they win. Another side comes in and says, "Well, wait a minute. That statute conflicts with the Constitution of the United States, therefore, Court, don't pay attention to what that statute says. It doesn't actually count in this case, not because it isn't law, but because it's been trumped by something that's also law, the Constitution, but that is hierarchically higher and so wins in a conflict.” That is the essence of what we call "judicial review." Judicial review is simply a recognition by courts that if there is a conflict between the Constitution and any of the other sources of law: statutes, regulations, common law, whatever they may be, the Constitution is supposed to win that conflict. It's higher up in the hierarchy of values. And put that way, the source of the power of judicial review is the grant of the judicial power, so the power to decide cases in accordance with governing law. Well, what's the governing law? You gotta figure out what the governing law is. Part of the process of figuring out the governing law is figuring out which of different sources pointing in different directions trump each other. What's the highest trump? What's the ace of trumps? What's the thing that beats everything else? That happens to be the Constitution. Hence, judicial review. Right? So it's not that mysterious or complicated a thing. You don't need a specific clause in the Constitution that's a judicial review clause, because the grant of the judicial power already includes it. Notice the consequences of judicial review. We often say that when courts prefer the Constitution to statutes, they're striking down the statute. We don't, in those cases, take all of our copies of the United States code and rip out the pages that have the statute and burn them. No, the statute stays there. It's just not being given effect in this particular case. It's still law, counts as law, went through the Article 1 Section 7 process. The Constitution defines it as law. Just happens to have been beaten by something else that is also law: the Constitution, that wins out in that conflict. That's the essence and source of judicial review.