Under the Fourth Amendment of the United States Constitution, law enforcement officers must obtain a warrant before conducting a search. The Fourth Amendment guarantees your right to be free from unlawful searches and seizures.Participants will answer the question: Does the Fourth. From there, courts must presume that the invalid charge caused an unreasonable search or seizure. The fourth amendment requires all law enforcement in the United States to have probable articulable cause and knowledge of the law. But remember, even with "stop and identify" laws, police officers must have reasonable suspicion to believe a person committed a crime. The decision in Miranda v. Unfortunately, probable cause isn't always a clear rule, so a warrant may be issued based on an officer's word that probable cause exists. The impact of this is clear. Fourth Amendment: Traffic stop based on Officer Safety.