To speak about sources of law and documents, you need the appropriate vocabulary.
Legislation - a law or a set of laws;
Policy - an agreement that you have with an insurance company (= company that pays the costs if you are injured, etc);
Statute - a law or rule;
Precedent - an action or decision that is used as an example when someone wants to do a similar thing in the future;
Procedure - the official or usual way of doing something;
Intake memo - an informal record, in the form of a brief written note or outline, of a particular legal transaction or document for the purpose of aiding the parties in remembering particular points or for future reference;
Agreement - a promise or decision made between two or more people;
Agenda - a list of subjects that people will discuss at a meeting;
Medical record - information that is written on paper or stored on computer so that it can be used in the future;
Police report - a description of an event or situation written by the police.
Examples:
Most people want tougher environmental legislation but large corporations continue to oppose it.
This decision has set an important legal precedent for other countries.
The company has new procedures for dealing with complaints.