Coups d’etat: definition, issues, and relation with the literature
O’Kane (1987, pp. 22 and 37) defines coups as attempts to overthrow a government that are:(i) illegal; (ii) carried out by a small group based within the state apparatus; (iii) speedily effected; and (iv) involve the threat or actual use of violence (see also Luttwack, 1968, p. 27). This definition stresses the distinctive features of coups. First, the masses do not participate directly in their execution —coups are the business of an elite. Second, coups are swift events: Most of the time, either plotters succeed in taking control within 24 to 48 hours, or the coup attempt fails. Third, although some coups are bloody, many times the threat of force is enough to overthrow the incumbent. For this reason, the direct participation of the military is often not necessary, and coups staged and carried out by civilians are not uncommon. For example, O’Kane (1987, pp. 9, 10) stresses that only one government in six set up after a successful coup is composed exclusively by military officers. Most are a mixture of military officers and civilians.
Galetovi, A & Sanhueza , R 1999, ‘Citizens, Autocrats, and Plotters: A Model and New Evidence on Coups D’Etat’