This article is from the Lawful Arrest/Search/Seizure FAQ, by Ahimsa Dhamapada email@example.com with numerous contributions by others.
A justification or reason to arrest/search/seize, which
exists *PRIOR to the arrest*, usually described in a
document. The Warrant describes exactly what is to be
searched, or who/what is to be seized (and why!). All
proper arrests, searches, seizures need this in order
to be valid (except perhaps for some extremely rare
We often hear today of the multitude of conditions
under which a warrantless search or arrest can happen.
"It's OK, you see! The courts have approved it" (which,
by the way, is the same court that makes a "fine" profit
when you are found guilty of the charges).
A Warrant is more than a piece of paper. (And under the
present system, having the Warrant issued by a judge is
like putting the wolf in charge of protecting the sheep!)
Look up the word in any dictionary. Warrant means
"justification, reason". If there is no Warrant for
arrest, there is no "just reason" for arrest. There is no
Imagine a world where a Warrant is not needed! If there
is no Warrant to arrest, then there is no proof of
a valid reason to arrest. In such a system, nothing
would prevent the Occupying Force from setting up
blockades, and searching every ship (or automobile!),
and taking/impounding/stealing anything they please. This
common event today is what the Founders were trying to
prevent by the Fourth Amendment requirement of a specific
Note that the officer often obtains a "consent to search"
by asking, "Do you mind if I search your car?" This may
appear to waive the Constitutional requirement for a
Warrant, but it is very much in violation of the spirit
of it. Many people feel coerced into consenting, because
of fear of the consequences. Also, many people feel that
not consenting to a search implies guilt.
Further violations of the spirit of the Constitution:
having a dog or x-ray instruments, etc. perform the search;
Requiring "implied consent to search" in order to obtain
a Driver's License, etc.