One Jury, Twelve Jurors - Why Twelve?

Did you ever serve on a jury? You took your seat in aon the first bone of your right forefinger. The left hand
panel of twelve jurors solemnly sequestered behind akeeps the active tally (e.g. measures of peas, apples,
soundproof door. Then came a surprise. Seven jurorssausages, onions, turnips or livestock) while the right
reached the verdict. The others went with the majority.hand keeps track of the twelves to subtotal the
That was my experience. So why empanel twelve"bottom line." Twelve was the benchmark for
people to do the work of seven?commerce.
Blame King Henry II of England. Henry won the throneAnd the benchmark for juries! What was good for
of England in 1154 after nineteen years of civil war lefttrade was good for King Henry's justice. Henry
the country in ruins. He spent his first decade as kingachieved his reforms at a time of vicious discord with
restoring what years of strife had destroyed, includingThomas Becket, and with Eleanor, Henry's queen.
the judicial system. A man of tireless energy, HenryEleanor removed herself from Henry's court in England
worked with his chancellor, Thomas Becket, to createto protest his flouting his mistress, "Fair" Rosamond
a code of laws and penalties to be interpreted in newClifford.
county courts by incorruptible officers. Judicial systemsWe can imagine Eleanor saying, "Let Henry draft his
in many English-speaking countries descend from theConstitutions, his Assize! Let him prefer his twelve just
model that Henry wrote into law at Clarendon in 1166.men! Let him judge England!"
But why empanel exactly "twelve just men" to "reportFired by her own passion for reform, Eleanor set up
malefactors"? Henry's queen, Eleanor of Aquitaine,her Court of Ladies in her capital city, Poitiers, where
explains: "Henry showed populist leanings in curiouswomen debated "courtly love" and addressed their
ways. He set his legalists striving to codify therights, devising Eleanor's Code of Poitiers. "I imagined
common law, and twelve is the common measure infor women a state above strife and far above men.
the market-place."Would that our human estates were ruled by twelve
Indeed, twelve was the common market measure. Notjust women!"
ten. Counting ten fingers takes you to ten, and youThe supremacy of base-twelve in trade dates from
can't measure quarters and thirds in whole numbers.before the reign of Charlemagne, who died in 814.
But twelve, a dozen (douzaine), takes you to a gross,Charlemagne never ruled England, but good ideas
144, while whole numbers (multiples of three and four)travel. Henry II adopted base-twelve for English money
express quarters and thirds.as well as commerce. For nearly eight hundred years
Try it! Use your left thumb to tally the number of bonesa shilling was worth twelve pence.
in the other four fingers of that hand. You'll countSo! Measures of peas, grain, sausages, livestock,
twelve. Now transfer your left hand's score, twelve,pennies and jurors. All over the planet, jurors still file in
into "Memory" by using your right thumb to tally twelveand out of courts, in twelves.