When Congress passed and President Joe Biden (D) signed the recent debt ceiling bill, one of the items included was a requirement for construction on the Mountain Valley Pipeline to proceed to completion and for the pipeline to begin operation. In conjunction with that, the bill removed from lower courts their jurisdiction over questions  regarding the natural gas pipeline.

The Fourth Circuit, when “environmentalists” got their cases to it, blocked construction while it sorted out whether it could rule on the matter.

The Supreme Court has sorted the matter out for the Fourth Circuit, at least temporarily: the pipeline will be completed with no further delay; the Court has lifted the Circuit’s stay.

The “environmentalists'” beef was this, as paraphrased by The Wall Street Journal:

stopping legal challenges before the Fourth Circuit violated the separation of powers clause of the Constitution, in effect giving Congress the power to decide the outcome of judicial proceedings.

This would be risible, were it not so cynical. No judicial proceeding is being predetermined by Congress. What has been specified, as allowed under our Constitution, is the jurisdiction of courts below the Supreme Court; in this case, that lower courts do not have jurisdiction to hear cases involving the MVP. Nor have the courts as a whole been denied jurisdiction; such cases still can come before the Supreme Court, should that Court choose to hear them.