This was the vagueness challenge to the career offender guideline. Both the defendant and the government agreed that the guideline provision was vague and that the 11th should be reversed.  The Court had to appoint a lawyer to argue the contrary position, and ruled unanimously for that position:  Justice Thomas starts his majority opinion this way:

At the time of petitioner’s sentencing, the advisory Sentencing Guidelines included a residual clause defining a “crime of violence” as an offense that “involves conduct that presents a serious potential risk of physical injury to another.” United States Sentencing Commission, Guidelines Manual §4B1.2(a)(2) (Nov. 2006) (USSG).   This Court held in Johnson v. United States, 576 U. S. ___ (2015), that the identically worded residual clause in the Armed Career Criminal Act of 1984 (ACCA), 18 U.S.C. §924(e)(2)(B), was unconstitutionally vague. Petitioner contends that the Guidelines’ residual clause is also void for vagueness.  Because we hold that the advisory Guidelines are not subject to vagueness challenges under the Due Process Clause, we reject petitioner’s argument.