College students who reside in campus dormitories at public universities have a reasonable expectation of privacy in their dorm rooms that is protected by the fourth amendment; and officials cannot search these rooms for law enforcement purposes without a valid warrant. Non-students, however, have no such reasonable expectation of privacy in dormitory rooms that they have vacated or live in as guests in violation of college housing rules. A line of cases indicates that college and university officials may search students' dormitory rooms for non-law-enforcement purposes without offending the fourth amendment if the search is authorized by language in a housing contract or a reasonable regulation adopted to maintain safety, security, and an educational environment conducive to learning. The ninth Circuit has ruled that campus authorities may conduct searches in areas where students have objectively reasonable expectations of privacy without obtaining a warrant if officials are motivated by a "special need" to protect the university's security that is separate and apart from law enforcement concerns. The seventh Circuit has ruled that university student inspectors may conduct a "lawful regulatory search" of a dormitory room to advance "special needs" beyond the needs of law enforcement without the necessity of obtaining a warrant. However, campus officials cannot rely on language in their regulations or student-housing contracts to justify warrantless searches that are conducted pursuant to a criminal investigation. [Discussion questions developed by Alyse Gray Parker.]