Isn&#39;t a hung jury proof of reasonable doubt?
<p>I don't understand the logic with allowing additional trials after a hung jury.  Isn't the fact that the prosecution can't get 12 jurors to agree the accused is guilty proof that guilt was not proven beyond a reasonable doubt, and so he should be acquitted?</p>
<p>Why does a not guilty verdict have to be unanimous as well?</p>

<h3>No. It means the existence of reasonable doubt is in doubt...</h3>
<p>One cannot conclude the question of guilt in either direction, so one must try again to see if a different jury can answer the meta-question, to then answer the legal question of guilt.</p>
<h3>... or is not being addressed</h3>
<p>If only one person is voting against the consensus, or as many as are allowed by the jurisdiction, they are overruled. That's the allowance made for bias that has somehow reached the jury despite the filtering done beforehand.</p>
<p>If more people are voting against the majority so that consensus is not possible, it is potentially because someone has made up their mind on the question of guilt regardless of what (some significant part or the weight of) the evidence indicates, defeating the purpose of the trial and providing all the evidence.</p>
<p>A person not accounting for all the evidence can't be said to have reasonable doubt of guilt, since the doubt may be excluded by the remaining evidence. Similarly, guilt beyond reasonable doubt cannot be supported by only partial evidence, as exculpatory evidence may be among the part not accounted for.</p>
<h3>... or cannot be addressed by that jury at all.</h3>
<p>Finally, a jury split on the decision of how to weigh the evidence cannot claim either to have or to have dismissed reasonable doubt, because they cannot agree on what a reasonable doubt is, in the first place.</p>

united-states criminal-law