Of revealing or publicizing either substantially true

History and legal development
The terms in this law derive from the Larceny Act 1916 sections 29 - 31, which itself draws on the Libel Act 1843 and the Larceny Act 1861.^[45] For example, s.30 refers to a person who demands "with menaces or by force". An offence also existed in common law: for example in R. v Woodward (1707) it was stated that "Every extortion is an actual trespass, and an action of trespass will lie against a man for frighting another out of his money. If a man will make use of a process of law to terrify another out of his money, it is such a trespass as an indictment will lie." The 1805 case R v. Sodherton stated that a threat needed to be such that a "firm and prudent man" would be overcome by it, and concluded that "The law distinguishes between threats of actual violence against the person, or such other threats as a man of common firmness cannot stand against, and other sorts of threats. Money obtained in the former cases under the influence of such threats may amount to robbery, but not so in cases of threats of other kinds".^[45]
The origin of the modern offence lay in the 1723 Black Act,^[45] which addressed a group of notorious poachers and extortioners.^[46] In 1823 an Act^[which?] was passed that criminalised "demanding money or other valuable thing" (1823) where no reasonableness or menace was required, and in 1927 this was updated in a further Act^[which?] to cover "any letter or writing demanding of any person, with menaces, and without reasonable or probable cause", thus mentioning menaces for the first time in the context of blackmail.^[45] The 1827 offence was in turn replaced in 1837 by an offence concerning any person who "with menaces or by force, demand(s) any property of any person with intent to steal".^[45] In the Larceny Act 1916 the element of "taking" included taking by intimidation based on an earlier case R v. McGrath.^[45]
Before the enactment of section 21 of the Theft Act 1968, the word blackmail was not a legal term of art. The word was used by lawyers as a convenient way of referring to the offences under section 29 to 31 of the Larceny Act 1916,^[9] and those offences were commonly known as blackmail.^[47] But the word blackmail did not appear anywhere in that Act.^[9] In early legal history, the term appears to have referred to the extorted property itself, and included by reference both the perpetrator and the victim - the legal position was that the victim was as equally culpable as the extortioner, insofar as he/she had given in to extortion and thereby made it profitable to extort.^[45]
Hogan described these offences as "an ill-assorted collection of legislative bric a brac which the draftsmen of the 1916 Act put together with scissors and paste."^[48]
They were replaced in 1968 by section 21 of the Theft Act.