Under the border search doctrine, suspicionless border searches are per se reasonable. However, the Supreme Court has identified three situations in which they might not be per se reasonable, i.e., at least reasonable suspicion is required: (1) 'highly intrusive searches of the person;' (2) destructive searches of property; and (3) searches conducted in a 'particularly offensive' manner. Flores-Montano, 541 U.S. at 152-56 & n.2.
The Supreme Court has recognized that the 'dignity and privacy interests of the person being searched' at the border will on occasion demand 'some level of suspicion in the case of highly intrusive searches of the person.' Flores-Montano, 541 U.S. at 152. Likewise, the Court has explained that 'some searches of property are so destructive,' 'particularly offensive,' or overly intrusive in the manner in which they are carried out as to require particularized suspicion. Id. at 152, 154 n.2, 155-56; Montoya de Hernandez, 473 U.S. at 541. The Court has never defined the precise dimensions of a reasonable border search, instead pointing to the necessity of a case-by-case analysis. 'Reasonableness, when used in the context of a border search, is incapable of comprehensive definition or of mechanical application.' Duncan, ...