Origins and Background
If you read the text of the 4th Amendment you won’t find anything about the exclusionary rule. But starting with a case called Weeks v. U.S. (federal case in 1914) and Mapp v. Ohio (extending it to states in 1961), the Supreme Court created the exclusionary rule. Basically the rule holds that if an officer violates the 4th Amendment, that evidence cannot be admitted at trial. As the police want to catch and prosecute criminals, the rule is designed to deter police misconduct.
Application
To say that the exclusionary rule has been overused throughout the decades since Mapp is a bit of an understatement. The Supreme Court has had to advise lower courts that this rule is a “last resort,” not a “first impulse.” Recall that the 4th Amendment requires officers be “reasonable” in their searches and seizures. Can an officer make a mistake – sure… so long as it is reasonable. As the Court said in Illinois v. Rodriguez, the 4th Amendment does not require officers to always be correct, but always be reasonable.
So, when determining whether the exclusionary rule applies, make sure that the facts and circumstances show the police engaging in intentional or reckless misconduct. If not, then the exclusionary rule would serve no purpose – and have no application.
Legal Supplement
United States v. Calandra, 414 U. S. 338, 348 (1974),
[We have stated that this judicially created rule is]designed to safeguard Fourth Amendment rights generally through its deterrent effect.
Illinois v. Krull, 480 U. S. 340 (1987),
[T]o the extent that application of the exclusionary rule could provide some incremental deterrent, that possible benefit must be weighed against [its] substantial social costs.
Illinois v. Rodriguez, 497 U.S. 177 (1990),
[The requirement of a police officer conducting a search or seizure under one of the exceptions to the warrant requirement] is not that they always be correct, but that they always be reasonable.
Pennsylvania Bd. of Probation and Parole v. Scott, 524 U.S. 357 (1998),
We have never suggested that the exclusionary rule must apply in every circumstance in which it might provide marginal deterrence.
[T]he rule's costly toll upon truth-seeking and law enforcement objectives presents a high obstacle for those urging [its] application.
Hudson v. Michigan, 547 U. S. 586, (2006),
Indeed, [Exclusion] has always been our last resort, not our first impulse …
Herring v. U.S., 555 U.S. 135 (2009),
[S]uppression is not an automatic consequence of a Fourth Amendment violation. Instead, the question turns on the culpability of the police and the potential of exclusion to deter wrongful police conduct.
Nonetheless, our decisions establish an exclusionary rule that, when applicable, forbids the use of improperly obtained evidence at trial.
The fact that a Fourth Amendment violation occurred--i.e., that a search or arrest was unreasonable--does not necessarily mean that the exclusionary rule applies.
First, the exclusionary rule is not an individual right and applies only where it " 'result[s] in appreciable deterrence.' " We have repeatedly rejected the argument that exclusion is a necessary consequence of a Fourth Amendment violation.
In addition, the benefits of deterrence must outweigh the costs. The principal cost of applying the rule is, of course, letting guilty and possibly dangerous defendants go free--something that "offends basic concepts of the criminal justice system."
To trigger the exclusionary rule, police conduct must be sufficiently deliberate that exclusion can meaningfully deter it, and sufficiently culpable that such deterrence is worth the price paid by the justice system. As laid out in our cases, the exclusionary rule serves to deter deliberate, reckless, or grossly negligent conduct, or in some circumstances recurring or systemic negligence.
