In the United States, is there a difference between the terms &quot;unlawful&quot; and &quot;illegal&quot;?
<p>I heard someone claim that the terms &quot;unlawful&quot; and &quot;illegal&quot; have different meanings. More specifically, they claimed that &quot;illegal&quot; acts are anything expressly forbidden in law (e.g. murder), while &quot;unlawful&quot; acts are anything not expressly permitted in law (e.g. wearing a hat).</p>
<p>This seemed unusual to me, and most dictionaries I could defined &quot;unlawful&quot; as basically synonymous with &quot;illegal&quot;.</p>
<p>While there doesn't appear to be any real difference between the terms in &quot;normal&quot; speech, is there any difference in &quot;legalese&quot;?</p>

<h2>Yes, but the difference is in nuance, not substance</h2>
<p><a href="https://www.merriam-webster.com/dictionary/illegal" rel="nofollow noreferrer">Illegal</a> means “not according to or authorized by law” and lists unlawful as a synonym.</p>
<p><a href="https://www.merriam-webster.com/dictionary/unlawful" rel="nofollow noreferrer">Unlawful</a> means “not lawful” with illegal as a synonym.</p>
<p>So, by definition, they mean the same thing and can be used interchangeably.</p>
<p>Illegal does carry a slight hint of being more egregious than unlawful and would be more often used of criminality than of a parking offense but it’s not wrong to use them interchangeably.</p>

united-states legal-terms