Misprision of felony
|Scope of criminal liability|
|Seriousness of offense|
|Offence against the person|
|Crimes against property|
|Crimes against justice|
|Crimes against animals|
|Defences to liability|
|Other common-law areas|
Exceptions were made for close family members of the felon.
A person was not obliged to disclose his knowledge of a felony where the disclosure would tend to incriminate him of that offence or another.
With the development of the modern law, this crime has been discarded in many jurisdictions, and is generally only applied against persons placed in a special position of authority or responsibility. In this case, the offence of misfeasance in public office or malfeasance in public office may be considered instead. For example, corrections officers who stand idly by while drug trafficking occurs within the prison may be prosecuted for this crime.
It has been abolished in England and Wales, in Northern Ireland, in the Republic of Ireland, and in New South Wales and other Australian States and Territories, but has often been replaced by a statutory offence.
United States federal law
Whoever, having knowledge of the actual commission of a felony cognizable by a court of the United States, conceals and does not as soon as possible make known the same to some judge or other person in civil or military authority under the United States, shall be fined under this title or imprisoned not more than three years, or both.
This offense, however, requires active concealment of a known felony rather than merely failing to report it.
If one knows that one is a target of an Federal investigation, it is illegal under the Sarbanes-Oxley Act to erase one's browser history intentionally. Khairullozhan Matanov was prosecuted for erasing computer records about his friends, Dzhokhar and Tamerlan Tsarnaev; he pleaded guilty to a lesser included offense in 2015.
The Federal misprision of felony statute is usually only used in prosecutions against defendants who have a special duty to report a crime, such as a government official.
- Sykes v. Director of Public Prosecutions  A.C. 582
- R v. King  1 All ER 1053
- The Criminal Law Act 1967 (c.58), section 1
- The Criminal Law Act (Northern Ireland) 1967 (c.18) (N.I.), section 1
- The Criminal Law Act 1997 (No.14), section 3
- The Crimes Act 1900, section 341 
- See United States v. Johnson, 546 F.2d 1225 (5th Cir. 1977) at 1227 ("The mere failure to report a felony is not sufficient to constitute a violation of 18 U.S.C.A. § 4."
- Devries, Juliana (June 2, 2015). "You can be prosecuted for clearing your browser history". The Nation. Retrieved June 8, 2015.
- Krotor (pseudonym) (June 8, 2015). "Clear your browser history and spend 20 years in prison". Daily Kos. Retrieved June 8, 2015.
- Smith, Jeff (April 7, 2014). "Chris Christie Is Toast: Federal prosecutors have their teeth in the New Jersey governor's close associates. And they ain't letting go". Politico. Retrieved April 8, 2014.
- Curenton, The Past, Present, and Future of 18 U.S.C. Sec. 4: An Exploration of the Federal Misprision of Felony Statute, (2003) Vol. 55 Alabama Law Review, 183.
- U.S. Code Online via GPO Access (wais.access.gpo.gov) United States Code Title 18, Part I, Chapter I, Section 4
- For a discussion of the appellant's defence and the decision in Sykes above, see P.R.Glazebrook, Misprision of Felony - Shadow or Phantom, The American Journal of Legal History, Volume 8, No.3 (July 1964) pp. 189 – 208, Temple University JSTOR
- For a general discussion of this offence from an American viewpoint, see William Lawrence Clark, A Treatise on the Law of Crimes, Hein, 1996, para. 439 pp. 679 – 680