Parallel construction
Parallel construction is a law enforcement process of building a parallel, or separate, evidentiary basis for a criminal investigation in order to limit disclosure as to the origins of an investigation. In the US, a particular form is evidence laundering, where one police officer obtains evidence via means that are in violation of the Fourth Amendment's protection against unreasonable searches and seizures, and then passes it on to another officer, who builds on it and gets it accepted by the court under the good-faith exception as applied to the second officer.