mistrial

from WordNet (r) 3.0 (2006)

mistrial
    n 1: a trial that is invalid or inconclusive

from The Collaborative International Dictionary of English v.0.48

Mistrial \Mis*tri"al\, n. (Law)
   A false or erroneous trial; a trial which has no result; a
   trial which comes to no conclusion, such as a criminal trial
   which does not produce a unanimous verdict of the jurors.
   [1913 Webster +PJC]