This is because the window is viewable by anyone one walking along that street. For example in Katz v. United States, a case ruled by the Supreme Court that there was no search if a person has an expectation of privacy and this expectation should be reasonable. For this case, if a police officer looks through the garbage, this cannot be termed as a search since there is not expectation that the garbage is private. The Congress has already placed statutory restrictions on incidents like when a police officer monitors telephone numbers dialed by individuals. At one time, the Supreme Court ruled in the case of Florida v. Riley, where police officers had hovered above a suspect's house with a helicopter and conducted surveillance. There can be no expectation of privacy in illegal activities. For example where a police officer uses a drug sniffing dog to investigate an illegal activity is not a search.
Under certain circumstances, it is not necessary for warrant for a search or seizure. For this case, the police officer must have a probable cause that makes him believe that the object in question is contraband before the search and seizure. There is search without a warrant on open fields if at all; the person conducting his activity in the open field had no reasonable expectation of privacy. ...Show more