United States v. Leon 468 U.S. 897, 104 S.Ct. 3405, 82 L.Ed.2d 677 (1984)
The police had received a tip
that Stewart and Sanchez were dealing drugs. They began watching who came
to their house.
Leon and DeCastillio were
Based on their frequent
visits, and a tip from a second informant, the police got a judge to issue
a search warrant.
The search turned up a big
pile of drugs and Leon and DelCastillo were arrested on suspicion of drug
At trial, Leon argued that the
search was illegal because the anonymous tip and the surveillance were
insufficient to create probable cause.
Because the search warrant
was held to have been invalid, all of the evidence stemming from that search
warrant is inadmissible based on the exclusionary
The exclusionary rule basically says that illegally seized evidence
should not be admissible as a policy, because it would deter law
enforcement officials from obtaining evidence by any means necessary.
The trial judge allowed the
evidence to be admitted.
Leon was convicted of drug
trafficking. He appealed.
The Appellate Court reversed
and excluded all of the evidence based on the search warrant. The
The US Supreme Court reversed
and found that the evidence was admissible even though the search
warrant was found to be deficient.
The US Supreme Court found
that evidence seized on the basis of an invalid search warrant was still admissible. As a matter of policy,
the exclusionary rule doesn't
have a deterrent effect if the police are acting in good faith and are following the rules to the best of
Since the exclusionary
rule is solely meant to deter
illegal police conduct, not punish errors, it is not the right remedy
for this situation.
No matter what punishment
is given, you can't deter honest mistakes.
This case said that the exclusionary
rule is there to be a deterrent, it
is not there to be a remedy.
The Court found that since
letting obviously guilty people go free has a societal cost, and subverts
the rule of law, on balance, the costs of the exclusionary rule outweigh the benefits in cases such as this.
Turns out, if you look at
the statistics, the costs are very small. Very few criminals are freed
because of a successful motion to suppress based on a search and seizure
The Court also felt that
since the job of the police is to catch criminals, they have a bias.
However, the job of the magistrates who issue the warrants is to achieve
justice, so they are more likely to be impartial. Therefore, if a
magistrate issues a warrant, it is probably because he thinks it is the
right thing to do.
The assumption is that
magistrates don't have the same anti-crime bias that the police do, but
is that true?
The basic rule is that unless
a warrant is grounded upon an affidavit knowingly or recklessly false,
evidence obtained pursuant to that warrant will be admissible.
Aka the good faith
"The suppression of
evidence obtained pursuant to a warrant should be ordered only on a
case-by-case basis and only in those unusual cases in which exclusion
will further the purposes of the exclusionary rule."
Btw, the warrant has to be
properly executed in order to qualify.
This is an objective
standard. The question that the judge must ask is not whether the particular
policeman would know there was no probably cause, but whether a reasonable
policeman would know that there was
no probable cause.
In a dissent it was argued
that the judiciary was part of the whole process, and by the time the case
reaches them they know that the warrant is not valid. Therefore, if they
admit the evidence then they are acting on information they know to be
false and are acting on an affidavit they know to be false.
In a dissent it was argued
that this decision would encourage the police to approach judges with only
the minimum amount of information in future warrant applications, and
reduce probable cause to not
entirely unreasonable cause.
Btw, the good faith
exception only applies to situations
where the police need a warrant. There are situations where the police
need probable cause but not a warrant (like if they believe that someone
is currently being attacked inside a house). In those cases, if the
police are found to have been mistaken about the probable cause, they are not protected by the good faith exception.