Civics
The Fourth Amendment of the U.S. Constitution: A Primer
Your Protection From Being Unreasonably Searched, Stopped, or Arrested
History:
The Fourth Amendment to the United States Constitution was enacted in 1791, four years after
the Constitution was created by the Constitutional Convention in Philadelphia. The Fourth
Amendment expresses Americans’ commitment to protecting individual privacy and property
rights against unjustified interference by the government – “interference” usually referring to
you being stopped, searched or arrested or having your property searched or held. The Fourth
Amendment contains the following guarantee:
“The right of the people to be secure in their persons,
houses, papers and effects, against unreasonable searches and
seizures, shall not be violated, and no warrants shall issue, but
upon probable cause….”
Important Terms in Fourth Amendement:
* “Search” and “Seizure”
It is important to understand the terms “search” and “seizure” as they are used in the Fourth
Amendment. A search is conducted by a government officer (most often a police officer), and
involves an intentional touching or a rummaging in order to discover evidence or a weapon. A
seizure by a government officer is also on purpose, and it involves taking complete control over
the thing seized – evidence, contraband (an illegal item: narcotics, unlicensed weapons, etc), or
a person. A seizure of a person that lasts for a particular amount of time is known as an arrest.
* “Unreasonable Searches” and “Probable Cause”
The Fourth Amendment protects Americans against unreasonable searches and seizures. An
unreasonable search or seizure is one that doesn’t make sense to a reasonable (neutral, openminded) person. As a general rule, this means that a search and seizure must be supported by
two things: a warrant and probable cause. A warrant is a piece of paper, signed by a judge,
that allows police officers to search a place or a person, or to arrest a person. A judge will only
sign a warrant if the police officer who asks for the warrant has probable cause. A police
officer has probable cause if, looking at all the facts, a reasonable person would believe:
The police officer will find contraband or evidence in the place she wants to search,
or a criminal as the result of an arrest.
Stay Out of My House!:
Under the Fourth Amendment, your home is a sacred place and gets the strongest protection
under the Fourth Amendment. The police may never enter your home – whether it’s a house,
an apartment, a dorm room, even a hotel room -- unless:
1.
2.
3.
4.
You ask or invite them in; or
You consent or agree to their coming in; or
They have a warrant; or
Their entry is necessary to prevent imminent (about to happen) harm or death of
others. This is known as a search and seizure under emergency circumstances.
What Happens When I Leave My House? Less Protection . . .:
Other places and spaces have weaker protection against police entry. For example, if you
commit a crime in a public place the police may “seize” you there without an arrest warrant. If
you are driving or are a passenger in an automobile, the police may temporarily “seize,” or
stop, you if they are suspicious of your behavior. This is known as a traffic stop (more on this
later). And if you are walking down the street and a police officer reasonably believes your
behavior is suspicious, he may briefly stop you, question you, and even frisk you (pat down
your outer clothing) for weapons in order to satisfy his concern and assure his own safety in the
process. This is known as a stop and frisk.
Exceptions to the Probable Cause Rule:
* The Plain View Doctrine: Officer Sees, Officer Gets
Although the government usually may not search you or your belongings without probable
cause, there is an important exception to this rule called Plain View. If the police have the right
to be in a certain place, for example the sidewalk outside a person’s house, and by simply
looking through an open window see illegal activity, they may be able to enter the house
without a warrant. Or, if the police are already legally inside a person’s house and notice
evidence or contraband lying around in plain view, they can take those items and use them to
prosecute the resident. Or, if a police officer stops a person for a traffic violation and, looking
through an open window, sees contraband in the car, the officer can take the contraband and
even search the rest of the car, people in the car, and containers in the car (purses, glove
compartments, backpacks) for additional evidence.
* Search After Arrest: Get arrested, Get Searched
Another important exception to the probable cause rule takes place after a person is placed
under arrest for criminal activity. After an arrest, a police officer may search that person’s body
(usually by frisking him or her) and any area within reach of the arrested person (“grab area”),
to make sure the arrested person is not carrying a weapon, evidence, or contraband. This
exception is known as a Search After Arrest. After an arrest, the police may also make a
Protective Sweep of areas closely surrounding the scene of the arrest to make sure that there is
no other person or weapon present that could harm the police or the person who has been
arrested. This means that if the police arrest a person in her home, they may search the closets
in the arrest room, the hallways outside, and even other rooms leading to the home’s exit door.
KNOW YOUR RIGHTS: You can maximize your Fourth Amendment protections by following a
few simple rules:
(1) Never invite the police into your home unless you absolutely require their assistance.
(2) If the police come to your home and ask to speak with you, do not admit them; step
outside your home to talk, and close the door behind you.
(3) If the police come to your home and claim they have a warrant to search, ask to see the
warrant and read it. Make sure the warrant is for your address, and make sure you
know exactly what the police are entitled to look for.
(4) If a police officer approaches you in a public place and asks to search your belongings,
clearly state: “I do not consent to any searches.” Then ask the officer, “Am I free to
leave?” [Remember, however, that if you choose to enter a secure government building
or an airport, you must submit your person and belongings to the required screening
procedures.]
(5) When you are driving or a passenger in a car, you may be stopped at any time by a
police officer if you are not complying with traffic rules. Remember that traffic laws are
very lengthy and complicated, and it is almost impossible to obey all of them all of the
time. As a result, if a police officer wants to stop you in a car, he can usually find a
reason to do so. Unlike homes, cars have low privacy protection under the Fourth
Amendment because they are mobile (they can move quickly from place to place) and
potentially dangerous instruments. Because cars are usually small and carry only a few
people at a time, the law takes for granted that everyone inside the car is responsible
for everyone else’s behavior. This means that if the police stop a car carrying a driver
and a few passengers and there is an open bottle of beer in the front seat, the officer
can legally assume that both the driver and the passengers are drinking the beer. SO:
Drivers, make certain your cars are in good working order, and make certain you know
what your passengers are carrying in your cars. Passengers, make sure your drivers are
sober, licensed to drive, and not carrying contraband.
How do I evaluate 4th Amendment cases?

Is there a warrant?
o Yes – analyze evidence to determine if the warrant was issued with proper probable
cause
o No – Look for exceptions.
 Consent: Did someone consent to a search?
 Plain View: Was evidence of illegal activity in plain sight from a spot where the
officer was legally positioned?
 Emergency: Was there an emergency that required government official to
search
 Search after Arrest:
 Grab Area
 Protective Sweep
 Personal Body
Civics
Vocabulary Reference Sheet
4th Amendment Terms
1. Search – A touching or rummaging in order to discover evidence or weapons.
2. Seizure – Asserting complete control and authority over an object or a person.
3. Contraband – An illegal object or thing.
4. Warrant – A piece of paper, signed by a judge, that authorizes the police to conduct
a search and/or make a seizure.
5. Probable Cause – What a police officer must be able to demonstrate or show before
s/he can make a search or an arrest. Basically, a police officer must be able to show
that s/he will probably find evidence of a crime during a search, or a criminal as the
result of an arrest.
6. Consent – Agreement or acceptance.
7. Frisk – A “pat down” by the police of one’s outer clothing. A light search.
8. Plain View – The rule that lets police officers seize evidence and weapons that are
placed out in the open, even when the police don’t have a warrant.
9. Search After Arrest – The rule that lets police officers search the body and grab area
of an arrested person immediately following the arrest.
10. Protective Sweep – The rule that lets police officers search the immediate
surroundings after arresting a person, even if the surroundings are a private home.