Five Justices of our nation's highest court have now provided a definition of "Waters of the United States" that will be binding on the Executive and Judicial Branches at least until Congress says otherwise.  As Justice Alito, writing for the majority in Sackett v. EPA, and concurring Justices Kavanaugh and Kagan point out, the Court's definition shortens the reach of the Clean Water Act further than it has been shortened since 1977.

For years I've been writing that Congress could have avoided this result by stating its intention regarding the modern reach of the Clean Water Act in the face of the volleying that has been going on between the Judicial and Executive Branches for the past several decades as chronicled by Justices Alito and Kavanaugh in their opinions.

The good news is that three of the five Justices in the majority, and four of the concurring Justices, remain open to the idea that Congress can still do its job. The Court repeats language it has been using quite a bit in recent years, saying that it "require[s] Congress to enact exceedingly clear language if it wishes to significantly alter the balance between federal and state power and the power of the Government over private property" which is what it says a broader definition of Waters of the United States would do.

But the majority doesn't mention a constitutional limitation on Congress's ability to affect those balances in the interest of the protection of the environment so long as it is clear about it.

Some of you may recall that the Sacketts had argued for a two part test to determine the reach of the Clean Water Act that included a reference to the Constitution's Commerce Clause limit on the Federal Government's powers.

The less good news is that concurring Justices Thomas and Gorsuch very much have the Commerce Clause on their minds. Mostly by reference to judicial opinions that are more than one hundred years old, these Justices say that Congress's authority is constitutionally limited to regulating water "channels-of commerce." They bemoan that "the EPA (of its own license) and the Corps [of Engineers] (under the compulsion of an unreasoned and since discredited District Court order) have . . . . completely ignore[d] navigability and instead expand[ed] the CWA's coverage to the outer limits of the Court's New Deal-era Commerce Clause precedents."

And so, if (and that's a big "if") Congress were to decide to refresh the Clean Water Act as it has refreshed every other major environmental protection statute of the 1970s, how far can it go? Will the "Court's New Deal-era Commerce Clause precedents" that have been the law for our entire lives endure? Or will three other Justices join Justices Thomas and Gorsuch in reversing what they see as "deeper problems with the Court's Commerce Clause jurisprudence" which they say may be most evident in federal environmental law. Human health and the environment may hinge on the answer to these questions.

Authors Note: To hear more about the Supreme Court's Sackett opinions and what they mean, join an all-star panel and me next Wednesday at 1 pm EDT for an ALI CLE/ACOEL/FNREL sponsored presentation. For more information, visit