Because there were 12 Apostles? Really?

October 21, 2010 1:54 PM

Why twelve jurors? Why not eleven, or thirteen? My google-fu has only uncovered suggestions that it is because there were twelve apostles. I can't find a reliable source for that and it seems odd. Does anyone know?
posted by bearwife to law & government (15 answers total)

As close to an answer as you're likely to get.
posted by ewiar at 2:00 PM on October 21, 2010

There aren't necessarily 12 jurors. The Supreme Court has held that there need to be at least 6, and there are often as many as 36. Plus alternates, of course.

Grand juries are likewise all over the map.
posted by jedicus at 2:03 PM on October 21, 2010

Sorry, not 36. I misread a source. There are, however, juries of 18.
posted by jedicus at 2:09 PM on October 21, 2010

The US Supreme Court couldn't figure it out either.
"...while sometime in the 14th century the size of the jury at common law came to be fixed generally at 12, that particular feature of the jury system appears to have been a historical accident"
posted by zombiedance at 2:32 PM on October 21, 2010 [1 favorite]

A small number (two or three, for example) would not be representative enough and would produce quirky results. A large number (40, for example) would be much more representative of the population but would be unmanageable -- you would have to find 40 eligible people and detain them for the duration of the trial. It had to be something in between.

The ancients regarded 12 as a rather special number, as can be seen in astrology and religion dating back at least to the early Greeks. Odin had 12 sons, Israel had 12 tribes, Jesus had 12 apostles, Olympus had 12 primary gods, and the zodiac has 12 signs, whether you're Chinese or Indian or British.

And 12 is big enough to be representative of a general population but small enough, we have found over the years, to be manageable.
posted by pracowity at 2:33 PM on October 21, 2010

Obviously having an odd number of jurors would eliminate the possibility of a split decision. Juries have to reach a majority, so an even number allows a "no verdict" verdict.

Why 12? 12 is a dozen, and the dozen is a very old unit. Wiki: The dozen may be one of the earliest primitive groupings, perhaps because there are approximately a dozen cycles of the moon or months in a cycle of the sun or year.
posted by 7-7 at 2:49 PM on October 21, 2010

Obviously having an odd number of jurors would eliminate the possibility of a split decision. Juries have to reach a majority, so an even number allows a "no verdict" verdict

In most situations, the verdict must be unanimous.
posted by Ironmouth at 3:06 PM on October 21, 2010 [1 favorite]

Some states permit non-unanimous decisions. In Oregon in a criminal trial, 10-2 for conviction or 9-3 for acquittal is a decision, not a hung jury. But no state uses simply majority for juries. That isn't certain enough.
posted by Chocolate Pickle at 3:15 PM on October 21, 2010

Right. A majority isn't always sufficient, but it is always necessary.
posted by 7-7 at 3:57 PM on October 21, 2010

The modern idea of a jury (a group of strangers who are summoned to hear a case and determine the facts) was quite a late development in common law. My reading indicates that it evolved out of two similar institutions: compurgation or wager of law, which tested a defendant by forcing him to get twelve people (including himself) to testify to his innocence; and panels of twelve neighbours which were assembled to testify about things known to them - who owned what land, what rights they had, things like that.

What prompted the rise of the modern jury system was two events: the Church stopped using trial by ordeal to test criminals (the threat of forcing someone to put their hand in boiling water as a means of testing whether they are telling the truth); and plaintiffs started using the central courts in Westminster in preference to the local ones. This move meant that defendants could no longer be required neighbours to testify to their innocence: instead they would just hire eleven professional witnesses who could swear to anything they were asked. Anyway, the courts needed a new system of proof to replace the old ones and it adopted a form of our modern jury system - with twelve people, just like the older forms. Why did they use twelve people? Because twelve is a lucky number, I suppose, which is why there were twelve pence in a shilling, twelve inches in a foot, and twelve troy ounces in a troy pound.
posted by Joe in Australia at 6:10 PM on October 21, 2010

We've got 15 in criminal trials in Scotland. No hung juries there!
(Plus, jury selection is by lot. Pretty much the only thing that disqualifies you for duty is if you know one of the defendants. Jury selection? None of that.)
posted by scruss at 7:42 PM on October 21, 2010

My theory?

The reason why you don't invite thirteen to a party is that it is an awkward number. Twelve or less stay as one group. Fourteen or more break up into multiple groups.

Therefore, twelve is the largest number of people that will remain in one group, pretty much the optimal number for a jury.
posted by rakish_yet_centered at 7:51 PM on October 21, 2010

In 1852's History of Trial by Jury, William Forsyth and Appleton Morgan write, following a brief discussion of which culture brought the system to England:

The opinion of one of the latest and ablest of our legal writers, Mr. Serjeant Stephen, seems to coincide with that of Reeves, for he says, ' The most probable theory seems to be that we owe the germ of this (as of so many of our institutions) to the Normans, and that it was derived by them from Scandinavian tribunals, where the judicial number of twelve was always held in great veneration.'

John Proffatt wrote of these at length in 1872's A treatise on trial by jury: including questions of law and fact : with an introductory chapter on the origin and history of the jury trial thusly:

§ 9. Ancient Scandinavian Tribunals. — The tribunals of the people of the northern parts of Europe had, in ancient times, a popular character. This was a distinctive feature, thus corresponding to the general rule in the formation of such tribunals, already pointed out. From the larger body called together to represent a certain district, a smaller section, or committee, was appointed, as a special tribunal for the administration of law, and, in some cases, for the enactment of a law.... There were many characteristics about these ancient tribunals that show a remarkable and a very close analogy to our trial by jury. They were generally composed of twelve or some multiple of twelve;² they were selected from the general list of freemen of the district, who had a right to attend the general assembly; they were sworn to give a true verdict upon the facts submitted to them; and in most cases were subject to the approval of litigants.

² Twelve was not only the common number throughout Europe, but was the favorite number in every branch of the polity and jurisprudence of the Gothic nations.

The singular unanimity in the selection of the number twelve to compose certain judicial bodies, is a remarkable fact in the history of many nations. Many have sought to account for this general custom, and some have bused it on religious grounds. One of the ancient kings of Wales, Morgan of Gla-Morgan, to whom is accredited the adoption of the trial by jury in A. D. 725, dills it the -' Apostolic Law." " For," said he, " as Christ and his twelve apostles were finally to judge the world, so human tribunals should be composed of the king and twelve wise men." Forsyth, Trial by Jury, p. 46.

Full circle, then.

It's difficult to, as the Supreme Court warns, give great credence to ex-post-facto interpretations, which may have been influenced by the tenor of their own times. But it's probably impossible to know for certain. We do know that the ancients liked round numbers and particularly multiply divisible non-primes for a lot of things. From an exegetic standpoint, it's almost certainly the case that numerology -- the Hebrew Bible is thick with it -- chose the number of apostles to be twelve than the other way around.
posted by dhartung at 10:15 PM on October 21, 2010 [1 favorite]

Every State is different. In Oregon, misdemeanor trials have 6 jurors and require a unanimous verdict either way - guilt or not guilty. Any other split is a hung jury and the DA can decide to re-try the case. Felony trials are 12 jurors and they require at a minimum a 10-2 split for guilty or not guilty. Oregon and Louisiana are the only two states that allow non-unanimous jury verdicts.
posted by miss meg at 12:17 AM on October 23, 2010

I was on a jury of 10. Go figure.
posted by CodeMonkey at 11:50 AM on October 23, 2010