Notable SCOTUS debate over "obstruction of justice" in Pugin immigration case producing distinctive 6-3 divide

Though not the biggest case of interest to the federal criminal justice bar handed down by the Supreme Curt today (that's Jones v. Hendrix to be covered in coming posts), criminal justice fans will still want to check out SCOTUS's work in Pugin v. Garland, No. 22-23 (S. Ct. June 22, 2023) (available here).  Here is how Justice Kavanaugh's opinion for the Court gets started:

Federal law provides that noncitizens convicted of an “aggravated felony” are removable from the United States. The definition of “aggravated felony” includes federal or state offenses “relating to obstruction of justice.” 8 U.S.C. § 1101(a)(43)(S).  The question here is whether an offense “relat[es] to obstruction of justice” under §1101(a)(43)(S) even if the offense does not require that an investigation or proceeding be pending.  That question arises because some obstruction offenses can occur when an investigation or proceeding is not pending, such as threatening a witness to prevent the witness from reporting a crime to the police.  We conclude that an offense may “relat[e] to obstruction of justice” under § 1101(a)(43)(S) even if the offense does not require that an investigation or proceeding be pending.

Six Justices are in the majority in Pugin, three in dissent, but not in the usual 6-3 arrangement.  Justice Jackson joined the majority (and authored a short concurrence), while Justice Sotomayor's dissent was joined by Justices Gorsuch and Kagan (though Justice Kagan jumped off the last part).  Here is how the dissent starts:

From early American laws, to dictionaries, to modern federal and state obstruction statutes, interference with an ongoing investigation or proceeding is at the core of what it means to be “an offense relating to obstruction of justice,” 8 U.S.C. § 1101(a)(43)(S).  The Court circumvents this ample evidence only by casting a wide net and then throwing back all but the bycatch.  That approach “turns the categorical approach on its head,” Esquivel-Quintana v. Sessions, 581 U.S. 385, 393 (2017), and subverts the commonly understood meaning of “obstruction of justice” when Congress enacted § 1101(a)(43)(S) in 1996.  I respectfully dissent.