What is the effect of Section 3A1.1(b) of the Criminal Code when a defendant is convicted of sexually assaulting elderly victims over the telephone?

In United States v. Caterno, 957 F.2d 681 (9th Cir.1992), this court reviewed and upheld a 3A1.1(b) enhancement, based on the age of the victims, to the sentence of a defendant who sold nearly worthless coins at collectible prices over the telephone. Some of his victims were elderly. In that case, we deferred to the district court's specific finding that the defendant should have known his victims were vulnerable because the defendant "used 'the telephone to get behind the defenses of people who are frequently old people, who are frequently ... people who don't have the ability to protect themselves.' " Id. at 684.

More recently, this court has interpreted 3A1.1(b) as creating a categorical sentence enhancement which may be applied solely because of the age of the victim. In United States v. Castellanos, 81 F.3d 108 (9th Cir.1996), this court interpreted 3A1.1(b) as comprising two distinct prongs, and reasoned that, under the first prong, age or physical or mental condition may make a victim vulnerable per se: