This article is from the Lawful Arrest/Search/Seizure FAQ, by Ahimsa Dhamapada firstname.lastname@example.org with numerous contributions by others.
This can be thought of as "The Cause of Police Action",
or "The Cause of State Action". From [Gifis]:
"Claim in Law sufficient to demand judicial attention."
The elements of a valid Claim are:
1: A right
2: An injury
3: A petition for compensation (money or property).
a.k.a., a "prayer for damages".
Once again, we see that before the force of the people/government
(the Police, the militia, etc.) can act, there should be
an injured victim, and a complaint by the injured party.
This notion has a long history, and is derived from
concepts in Common Law, the long unwritten legal code of
our ancient European ancestors.