The Collaborative International Dictionary of English v.0.48:

Depeach \De*peach"\, v. t. [L. d['e]p[^e]cher. See Dispatch.]
   To discharge. [Obs.]
   [1913 Webster]

         As soon as the party . . . before our justices shall be
         depeached.                               --Hakluyt.
   [1913 Webster]