The U.S. solicitor general has dual roles—as an advocate for the federal government and as an advisor to the justices of the U.S. Supreme Court.

Several times each term the justices formally invite the solicitor general to file a brief “expressing the views of the United States” in a case the Supreme Court has been asked to review.

Called a CVSG—or call for the views of the solicitor general—the court “usually, but by no means always” follows the recommendation of the SG, former Solicitor General Gregory Garre told Bloomberg BNA.

But the SG’s office fared worse than usual last term,...