>The purpose of the exclusionary rule and the "fruit of the poisonous tree" is to prevent the police from purposely violating the 4th amendment. There is no oth

>The purpose of the exclusionary rule and the "fruit of the poisonous tree" is to prevent the police from purposely violating the 4th amendment. There is no other reason why illegally obtained evidence shouldn't be used to convict a criminal. Even if we accept this, allowing the police to claim ignorance gives a loop hole to allow for illegally obtaining evidence. That is why the evidence must be obtained legally, not 'I thought it was legal but it wasn't'.