WASHINGTON – A federal law requiring longer prison sentences for using a gun during a "crime of violence" is unconstitutionally vague, a deeply divided Supreme Court ruled Monday.

The verdict divided not only the justices in general but President Donald Trump's two nominees in particular: Associate Justice Neil Gorsuch joined the court's four liberals and wrote the decision. Associate Justice Brett Kavanaugh delivered a fiery dissent for the court's other conservatives.

The Justice Department had warned that if the law was struck down, it "will inundate courts with collateral-review petitions by some of the most dangerous federal prisoners and will frustrate efforts to prosecute current and future violent criminals."

That argument was reinforced by Kavanaugh's dissent, which labeled the 5-4 ruling "an extraordinary event in this court."

"The court's decision today will make it harder to prosecute violent gun crimes in the future," he wrote. "The court's decision also will likely mean that thousands of inmates who committed violent gun crimes will be released far earlier than Congress specified."

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Gorsuch, however, has aligned himself with the court's liberal wing twice before this term and showed no hesitance in doing it again.

"In our constitutional order, a vague law is no law at all," he said in announcing the verdict from the bench.

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This article originally appeared on USA TODAY: Supreme Court says tough gun law is unconstitutionally vague, dividing Trump picks Gorsuch and Kavanaugh