(1) A person is guilty of blackmail if, with a view to gain for himself or another or with intent to cause loss to another, he makes any unwarranted demand with menaces; and for this purpose a demand with menaces is unwarranted unless the person making it does so in the belief—
(a) that he has reasonable grounds for making the demand; and
(b) that the use of the menaces is a proper means of reinforcing the demand.
(2) The nature of the act or omission demanded is immaterial, and it is also immaterial whether the menaces relate to action to be taken by the person making the demand.
(3) A person guilty of blackmail shall on conviction on indictment be liable to imprisonment for a term not exceeding fourteen years.