Concealment, neglect of. (French, mépris.)
Misprision of clerks.
Mistakes in accounts arising from neglect. Misprision of felony. Neglecting to reveal a felony when known. Misprision of treason. Neglecting to disclose or purposely concealing a treasonable design.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
More on Misprision from Infoplease: