The ACLU filed an amicus brief in this case, which concerns the warrant requirements of the state and federal constitutions and the question of whether these requirements permit police searches "into areas ordinarily private from government scrutiny" without consent of the person being searched, excepting extenuating circumstances which make a search warrant impossible. More specifically, they tackled the question of "the automobile exception," and the "inherent mobility of vehicles which frequently made it impracticable to obtain a search warrant without the sacrifice of other significant govenmental interests."

The Valdez case concerns an arrest made and contraband seized as a result of a warrantless search of an automobile. The contraband seized was in a paper bag, inside the trunk of the car. The case here concerns the specifics of whether this warrantless search violates certain clauses of the "automobile exception," including the "luggage rule" (items inside of closed containers can't be searched) and the "plain view rule" (objectionable items must be in plain view in order to justify a search). They argue: "There simply is no "automobile exception" to the Fourth Amendment exisiting apart from the exigent circumstances and plain view rules discussed above." The outcome of the case is not available in the documents provided.