[1] : The Collaborative International Dictionary of English v.0.48

pais \pa`is\ p.a`-e", n. of. pu"is, f. pays, country.
   o. e. law
   the country; the people of the neighborhood.
   1913 webster

   note: a trial per pais is a trial by the country, that is, by
         a jury; and matter in pais is matter triable by the
         country, or jury.
         1913 webster

[2] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

pais, or pays. a french word signifying country. in law, matter in pais is 
matter of fact in opposition to matter of record: a trial per pais, is a 
trial by the country, that is, by a jury. 

Pais >> P Words
Pais, definition of term: Pais
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