On its face, the vice principal's discovery of marijuana in his student's purse may seem like an easy one. After all, she was seen smoking in the girls' room, and when she denied it the vice principal went looking for evidence that proved the charges. One of the fundamental rules governing warrantless searches by the police is that they are allowable if there is probable cause that a crime has been committed. The teacher's observation would seem to offer more than probable cause. And once the vice principal was legitimately inside the girl's purse, another warrantless-search rule kicked into place—plain view. Anything found in plain view is considered legally obtained. In short, the vice principal's search would seem legitimate and the evidence discovered would seem usable in court.
But not so fast. Smoking was not actually forbidden at this high school; it was permitted in certain areas. The girl's infraction was smoking in an unauthorized area, not the act of smoking. This meant that there was no rule against carrying a pack of cigarettes. What purpose, then, was served by opening up the girl's purse? Even if the vice-principal found a pack of cigarettes, would this prove that the girl had broken a school rule? Would this prove that she was smoking in the bathroom? Moreover, the girl's lawyers argued that the vice principal found the drug evidence well after he saw the cigarettes lying on top—that only after digging through the purse did he find the evidence that would be used against her in court.
Ultimately, this case New Jersey v. T.L.O.) made its way to the United States Supreme Court in 1985. Reflecting, perhaps, the difficulty in drawing the line between the legitimate needs of school officials and the constitutional rights of students, the Court provided a somewhat mixed verdict. Students did have Fourth Amendment rights, the Court said; they were protected against unreasonable searches. But school officials, facing "major social problems" needed to be allowed certain flexibility in pursuing their responsibilities. Therefore, while students could not be searched unreasonably, the standard for conducting a warrantless search would be lowered. Teachers and administrators need not have "probable cause" that a crime had been committed in order to conduct a search. Instead, the search must only meet a standard of "reasonableness, under all of the circumstances." In practice, this meant that school officials only needed a reasonable suspicion that a school rule or law had been broken before conducting a search, and that the search itself must be reasonably conducted.
Not everyone agreed with the ruling. Two justices wrote dissents decrying the erosion of Fourth Amendment protections implicit in it. But others applauded the Court's ruling and sought to apply its logic to other student-search questions. Did the authority granted to school officials in New Jersey v. T.L.O. extend to searching student lockers? Would the ruling permit students to be strip-searched? Would it authorize school officials to search students' cars?
Generally, yes. When a student, smelling of marijuana and acting lethargically, was told to strip to his underwear to be searched, an Ohio court ruled that the procedure was embarrassing but reasonable. When school officials searched the car of a student who smelled of alcohol and acted drunk, an Alaska court ruled that it was reasonable under the circumstances. But a Texas court also demonstrated that the ruling in T.L.O. was not a blank check. When an administrator strip-searched a student, and then checked his locker and car, because the administrator had received information that the student was dealing drugs and because the student was trying to leave campus early, the court ruled that the search was not reasonable and therefore illegal. What all of these cases revealed was that the issue was less about the item being searched than the reasonableness of the search itself. If "all of the circumstances" surrounding the search suggested that a search was reasonable, purses, wallets, cars, and lockers could be inspected. They could even ask students to partially disrobe so long as the search was conducted in an age and gender appropriate fashion.