Supreme Court Justice Neil Gorsuch joined his liberal colleagues in a 5-4 ruling Monday, invalidating a federal law that criminalized the use of firearms in certain violent crimes.

Writing for the majority in United States v. Davis, Gorsuch held that the language of the law was vague and therefore inapplicable.

“In our constitutional order, a vague law is no law at all,” Gorsuch wrote. “Only the people’s elected representatives in Congress have the power to write new federal criminal laws. And when Congress exercises that power, it has to write statutes that give ordinary people fair warning about what the law demands of them. Vague laws transgress both of those constitutional requirements.”

The case involved two men convicted of multiple counts of robbery in 2014. Maurice Davis and Andre Glover were also found guilty of two counts of brandishing a shotgun during the "crime of violence," which the now defunct federal criminal statute defined as “any other offense that is a felony and that, by its nature, involves a substantial risk that physical force against the person or property of another may be used in the course of committing the offense.”

Under the law in question, those convicted of brandishing a firearm during a violent crime could receive a minimum sentence of seven years in addition to any sentence received for the underlying crime, plus an additional 10 years if the gun was fired. As a result, Glover and Davis were given stiffer penalties; Glover was sentenced to 41 years in prison and Davis to more than 50 years.

The ruling followed an earlier precedent: In Sessions v. Dimaya, the bench held that identical language in the federal definition of a crime of violence, Section 16(b), was unconstitutionally vague. It follows, then, that Section 924 is as well.

Gorsuch’s opinion is a reminder that it is the government’s responsibility to prove guilt, and the court’s duty to interpret that guilt under the narrow requirements of the law. The vagueness of the rule in question undermines this and thus the entire justice system: Its lack of coherence and range would allow courts to broadly interpret and extend the law’s reach beyond their constitutional means.

“In our republic,” Gorsuch wrote, “a speculative possibility that a man’s conduct violated the law should never be enough to justify taking his liberty.”

Justice Brett Kavanaugh dissented from Gorsuch and declared that this “theory seems to come out of nowhere,” calling Gorsuch’s “broadening/narrowing” principle “novel.”

Kavanaugh is right that there is no Supreme Court precedent declaring the courts’ duty is to narrow the interpretation of the law, not broaden it. But this principle existed long before Gorsuch articulated it. His opinion merely reinforces it.

Due process depends on limiting the sphere of the courts and Congress within the justice system. Thanks to Gorsuch's jurisprudence, that sphere just became a little more compact.