If you are facing criminal charges, it is important to understand different doctrines that may impact how the case proceeds. One of these doctrines is known as the fruit of the poisonous tree.
This essentially governs what evidence can and cannot be used in a criminal case. If evidence has been gathered legally by the authorities, then it can be used against you if your case goes to trial. But if the police illegally gathered that evidence, then the entire tree is poisoned. Illegally obtained evidence cannot be used in a trial, which may mean that the authorities do not have any evidence against you.
How could this happen?
One example of this is if the police perform an illegal search of your home. Maybe an officer believes that you are selling drugs and asks for your consent to come in and look around. You do not give them that consent, meaning the officer should go get a search warrant. Instead, that officer just forces their way inside and, sure enough, they find your supply of illegal drugs that you have been selling.
If the officer had gotten the search warrant in advance, this would be a major find for the prosecution. It may directly lead to a conviction because it shows that you are guilty of, at the very least, possessing illegal substances. But if those drugs were found through an illegal search, then they have to be omitted from the trial, so the officer may not have any other evidence that you actually broke the law.
This is just one example of how the fruit of the poisonous tree doctrine applies, but it helps to show why you need to know about all of your criminal defense options when facing charges.