For evidence to be admissible in a criminal prosecution it generally must have been obtained legally—with a search warrant, or based on an exception to the search warrant requirement, such as consent to search—and be relevant and reliable.
In Wyoming, as in other states, the admissibility of evidence in a criminal prosecution is governed by both state statutes and federal law, including the Fourth Amendment to the U.S. Constitution. Evidence must generally be obtained legally for it to be admissible in court. This means that law enforcement officers are typically required to obtain a search warrant before conducting a search that would otherwise violate an individual's reasonable expectation of privacy. However, there are several exceptions to this requirement, such as when an individual gives consent to a search, when evidence is in plain view, during exigent circumstances, or when the search is incident to a lawful arrest. Additionally, the evidence must be relevant to the case, meaning it must have a tendency to make a fact more or less probable than it would be without the evidence, and it must be reliable. Evidence obtained through illegal means, such as without a warrant when one is required and no exception applies, is likely to be excluded from trial under the exclusionary rule, which serves to deter police misconduct.