One of twelve in court (5)
I believe the answer is:
juror
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">one of twelve in court</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for juror that I've seen before include "person to deliver verdict" , "One of 12 in court" , "One of those responsible for verdict" , "Trial panellist" , "One empanelled in court" .)