2005 Federal Sentencing Guidelines
Chapter 2 - PART X - OTHER OFFENSES 
§2X4.1. Misprision of Felony
(a) Base Offense Level: 9 levels lower
  than the offense level for the underlying offense, but in no event less than 4,
  or more than 19.
Commentary
Statutory Provision: 18 U.S.C. § 4.
Application Notes:
1. "Underlying offense" means the offense as to which the defendant is convicted
  of committing the misprision. Apply the base offense level plus any applicable
  specific offense characteristics that were known, or reasonably should have
  been known, by the defendant; see Application
  Note 10 of the Commentary to §1B1.3 (Relevant Conduct).
2. The adjustment from §3B1.2 (Mitigating Role) normally would not apply
  because an adjustment for reduced culpability is incorporated in the base offense
  level.
Historical Note: Effective
  November 1, 1987. Amended effective November 1, 1989 (see Appendix
  C, amendment 244); November 1, 1993 (see Appendix
  C, amendment 496).