Is there an offence when you kill to prevent a murder?
<p>Suppose Person A shoots and kills Person B, who was about to shoot to kill Person C, and Person C makes a statement to police to say that if Person A hadn’t intervened, there was no doubt they would have died (i.e. Person B actually pulled the trigger, and only missed due to a bullet to the head).</p>

<p>In the United Kingdom, what crime could Person A be charged with? What might be the minimum sentence, if they can be found guilty?</p>

<h2><a href="https://en.wikipedia.org/wiki/Murder" rel="noreferrer">Murder</a></h2>

<p>Which is the unlawful taking of a life with intent to do so.</p>

<p>However, the doctrine of <a href="https://en.wikipedia.org/wiki/Self-defence_in_English_law" rel="noreferrer">self-defence</a> can make killing lawful:</p>

<blockquote>
  <p>A person may use such force as is reasonable in the circumstances in the prevention of crime, or in effecting or assisting in the lawful arrest of offenders or suspected offenders or of persons unlawfully at large.</p>
</blockquote>

<p>if the prosecutor is of the opinion that the force used "is reasonable in the circumstances" they may not lay charges. If they do lay charges the judge may decide that there is no case to answer before going to trial if self-defence applies. If there is a trial this will probably be the strategy the defence employs and they may or may not be successful.</p>

<p>If convicted the penalty is life imprisonment.</p>

<p>Also, there is no UK law: there is the law of England and Wales, the law of Scotland and the law of Northern Ireland.</p>

criminal-law united-kingdom is-x-legal homicide