The following excerpt is from U.S. v. Robertson, 833 F.2d 777 (9th Cir. 1987):
As to the later search, with a warrant, of the backpack, the court equates the backpack with a pocket on a pair of pants on a person. With the aid of this equation, the court finds decisive authority supporting its position. Ybarra v. Illinois, 444 U.S. 85, 90, 100 S.Ct. 338, 341, 62 L.Ed.2d 238 (1979). The equation is not justified, the authority is not apposite. Ybarra involved a search of a person's clothes. Clothes not only, as the adage has it, make the man; clothes are part of a way a person presents himself or herself; they are close enough to the person to be assimilated to the person. A backpack or bookbag, whatever sentiments may attach to it and however often it is lugged around by a youthful owner, is distinguishable.
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