In U.S. v. Gallegos-Aguerro, No. 04-14242 (May 18, 2005), the Court (Barkett, Hull, Wilson) held that Booker did not affect the viability of Almendarez-Torres v. U.S., 523 U.S. 224 (1998), and rejected the argument that a judge not make fact-findings concerning a prior conviction in order to enhance by 16 levels a sentence for a defendant convicted of illegal re-entry following a conviction for an aggravated felony. The Court found no Sixth Amendment error.
The Court noted that there was error under the Booker rule that the Guidelines are advisory, not mandatory. This error, however, was harmless. The district judge sentenced the defendant to the longest sentence permitted under his Guideline range, i.e. the maximum allowable. Hence, there was no actual prejudice to the defendant.