legislature
Why do laws often have a preamble with references to previous laws?
<p>Why do many decrees, laws and acts start with a preamble with references to previous regulations? For instance, from an <a href="https://eur-lex.europa.eu/TodayOJ/fallbackOJ/l_09020200325en.pdf" rel="nofollow noreferrer">EU commission regulation</a>:</p>
<blockquote>
<p>THE EUROPEAN COMMISSION,</p>
<p>Having regard to the Treaty on the Functioning of the European Union,</p>
<p>Having regard to Council Regulation (EC) No 246/2009 of 26 February 2009 on the application of Article 81(3) of the Treaty to certain categories of agreements, decisions and concerted practices between liner shipping companies (consortia) ( 1 ), and in particular Article 1 thereof,</p>
<p>After consulting the Advisory Committee on Restrictive Practices and Dominant Positions,</p>
<p>Whereas:</p>
<p>(1) Commission Regulation (EC) No 906/2009 ( 2 ) grants a block exemption to liner shipping consortia from the prohibition contained in Article 101(1) of the Treaty, subject to certain conditions. That Regulation applies until 25 April 2020.</p>
<p>[...]</p>
<p>HAS ADOPTED THIS REGULATION:</p>
<p>Article 1</p>
</blockquote>
<p>And then the actual regulation starts. What is the purpose of this preamble, since it does not seem to add anything with an actual practical effect? Is it just to serve as a reminder of other relevant acts for those reading the law?</p>

<p>Preamble specifies <strong>context</strong>.</p>

<p>That helps to correctly understand the scope of the law, interpret and apply it.</p>
