Jury nullification is a consequence of a fair and impartial jury system. Put most simply, it is the power of a criminal jury to return a not guilty verdict, even though the prosecution meets the legal burden for a guilty verdict. It often stems from changes in the societal moral compass, for instance, when an act is no longer deemed to be criminal by that day's standards. It is not, what one might call, an explicit right of a jury, but rather it is a necessary logical consequence of any system that purports to maintain a fair and impartial jury.