If you find yourself facing drug charges or any other type of criminal prosecution, the fruit of the poisonous tree doctrine could play a large part in terms of the evidence presented against you.
FindLaw explains that this long-established legal doctrine holds that the government cannot benefit from any evidence, i.e., fruit, its officers obtain as the result of an illegal search or seizure, i.e., poisonous tree. In other words, the judge must exclude any such evidence from your trial. The government cannot use it against you.
The fruit of the poisonous tree doctrine and its companion exclusionary rule all stem from the Fourth Amendment to the U.S. Constitution. This is the Amendment that establishes your right to remain free from unreasonable searches and seizures by government officers, officials and those working on their behalf.
Neither the Constitution nor any U.S. case law defines what constitutes an unreasonable search or seizure. Consequently, judges must decide the constitutionality of a search and seizure on a case-by-case basis. Nevertheless, warrantless searches are always suspect.
Keep in mind that the fruit of the poisonous tree doctrine applies to any and all evidence the government obtains as the result of an illegal search or seizure, not simply the evidence obtained at the time of the unconstitutional search or seizure.
For example, assume that officers search your car during a traffic stop and find illegal drugs in it. Based on this, they obtain a search warrant for your home and find more illegal drugs there. If you and your attorney can prove that the initial warrantless search of your car was unconstitutional, the court must, under the fruit of the poisonous tree doctrine, exclude not only the drugs found there but also the drugs found at your home.