Who can commit the crime?
The prosecution must have evidence to show that the suspect is a 'public officer'. There is no simple definition and each case must be assessed individually, taking into account the nature of the role, the duties carried out and the level of public trust involved.
The courts have been reluctant to provide a detailed definition of a public officer. The case-law contains an element of circularity, in that the cases tend to define a public officer as a person who carries out a public duty or has an office of trust. What may constitute a public duty or an office of trust must therefore be inferred from the facts of particular cases.
The judgment of Lord Mansfield in R v Bembridge (1783) 3 Doug KB 32 refers to a public officer having:
' an office of trust concerning the public, especially if attended with profit ... by whomever and in whatever way the officer is appointed'.
It does not seem that the person concerned must be the holder of an 'office' in a narrow or technical sense. The authorities suggest that it is the nature of the duties and the level of public trust involved that are relevant, rather than the manner or nature of appointment.
In R v Whitaker (1914) KB 1283 the court said:
'A public office holder is an officer who discharges any duty in the discharge of which the public are interested, more clearly so if he is paid out of a fund provided by the public.'
This approach was followed in a series of cases from other common law jurisdictions: R v Williams (1986) 39 WIR 129; R v Sacks  SALR 413; R v Boston (1923) 33 CLR 386.
In R v Dytham (1979) 1 QB 723 Lord Widgery CJ talked of 'a public officer who has an obligation to perform a duty'.
Remuneration is a significant factor, but not an essential element. In R v Belton  WLR (D) 283 the defendant was an unpaid voluntary member of the Independent Monitoring Board. The Court of Appeal held that remuneration was not an indispensable requirement for the holding of a public office, or for liability to prosecution for the offence of misconduct in a public office.
The fact that an individual was a volunteer might have a bearing on whether there had been wilful misconduct, but was only indicative rather than determinative of whether an individual held a public office.
The court in Attorney General's Reference No 3 of 2003  EWCA Crim 868 referred to the unfairness that could arise where people who carry out similar duties may or may not be liable to prosecution depending on whether they can be defined as 'public officers'. What were once purely public functions are now frequently carried out by employees in private employment. An example is the role of the court security officer.
The court declined to define a public officer, however, but said: 'This potential unfairness adds weight, in our view, to the conclusion that the offence should be strictly confined but we do not propose to develop the point or to consider further the question of what, for present purposes, constitutes a public office.'
The following have been accepted as holding a public office by the courts over several centuries:
Coroner (1675) R v Parker 2 Lev 140 Constable (1703) R v Wyatt 1 Salk 380 Accountant in the office of the Paymaster General (1783) R v Bembridge 3 Doug K.B. 32 Justice of the Peace (1791) R v Sainsbury 4 T.R 451 Executive or ministerial officer (1819) R v Friar 1 Chit.Rep (KB) 702 Gaoler (1827) R v Cope 6 A%E 226 Mayor or burgess (1828) Henly v Mayor of Lyme 5 Bing 91 Overseer of the poor (1891) R v Hall 1 QB 747 Army officer (1914) R v Whitaker 10 Cr.App.R.245 County Court registrar (district judge) (1968) R v Llewellyn-Jones 1 Q.B.429 Police officer (1979) R v Dytham 69 Cr.App.R.387 Council maintenance officer (1995) R v Bowden 4 All E.R 505 Local councillor (2004) R v Speechley  EWCA Crim 3067 Member of the Independent Monitoring Board for prisons (2010) R v Belton R v Belton  EWCA Crim 2857 This list is illustrative only of the roles or functions that have been accepted by the courts over the years as falling within the definition of public officer. Each case must be taken on its own facts. The comments of the Court of Appeal in Attorney General's Reference No 3 of 2003  EWCA Crim 868 must be borne in mind concerning potential unfairness. The court took into account the fact that public functions are now frequently carried out by employees in private employment, for example those concerned with security at courts and the transport of defendants. There was the potential for unfairness if those holding a public office, such as police officers, were to be liable to a sanction not applicable to those in private employment who do similar work.
It is extremely difficult to extract from the cases any general identifying features of public officers in a contemporary context. A person may fall within the meaning of a public officer where one or more of the following characteristics applies to a role or function that they exercise with respect to the public at large:
Judicial or quasi-judicial
Punitive Coercive Investigative Representative (of the public at large) Responsibility for public funds This list is not exhaustive and cannot be determinative of whether a person is properly described as a public officer, when acting in a particular capacity. The characteristics should be treated only as a guide and considered in the context of all the facts and circumstances of the particular case.