Inter-jurisdictional arrest issues (USA, UK)
<p>My question centers around this:</p>

<blockquote>
  <p>It may harm your defense if you do not mention when questioned, something you later rely on in court.</p>
</blockquote>

<p>Which is something I've heard told to arrested suspects in the UK. Here's my question. </p>

<p>If an American is arrested in the UK, and keeps his mouth shut despite the warning in the block quote, and (after the red tape with the consulates) stands trial in the UK, is his defense harmed, or is the simple explanation that "He is American, and treated UK officers like US officers," sufficient for the Jury?<br>
<a href="https://law.stackexchange.com/questions/7039/failing-to-mention-when-questioned-something-you-later-rely-on-in-court">This Question</a> seems to imply that yes, it ought to be, as the item in the quote is for the defendant's benefit. </p>

<p>I'm also interested in the reverse. Suppose a UK suspect is arrested in US, and remembering the UK warning, speaks to the police. However, because he isn't a lawyer, phrases some aspects of his speech in a less than ideal manner, which the officers later use against him in court. </p>

<p><strong>How, and to what extent, have the US and UK defendants harmed their defense?</strong> </p>

<h2>The law applies equally to everyone</h2>

<p>The fact that the person misunderstood the law is irrelevant irrespective of the reason for it. </p>

<p>That said, in both cases the person would have access to a lawyer and consular assistance who could explain the law to them.</p>

united-kingdom trial united-states