[6.47] Although sheriffs, bailiffs and other ministerial officers of the court are not exempt from liability for their tortious acts, nevertheless it may be a defence to an action in false imprisonment, trespass or conversion that the act was done in the execution of judicial process This defence may also be available where negligence is raised as a cause of action. The availability of the defence stems from the fact that such persons are charged by law with the service and execution of court processes, which not only precipitate but often necessitate invasions of personal and property rights.
The position at common law is that a sheriff or other officer of the court, acting strictly within the authority of a warrant issued by a superior court of record, is protected although the judgement on which a warrant is issued is invalid. So, a sheriff who effects a dispossession of the tenant of rent-controlled premises, and is then sued in trespass by the tenant, will have a defence if he or she produces the authority of the court to effect dispossession, although it may be that in the circumstances the tenant is lawfully entitled to possession. Nor is the sheriff affected if the judgement is subsequently reversed. But this does not mean that a sheriff is protected if the warrant itself is invalid; that is, where the judgement is valid but there is no legal authority to issue the particular warrant. Certainly, if the warrant is not signed and marked in the required manner and, probably, whenever the warrant does not bear on its face the accepted characteristics of a valid warrant and, possibly, whenever the warrant, as distinct from the judgment on which it is based, is void and not merely voidable, the sheriff has no protection.
Where the process is issued out of an inferior court, the officer acting under it is protected if the subject matter of the suit is within the general jurisdiction of the court and the warrant is regularly issued, even though the judgment itself might not be sustainable. In Ward v Murphy an officer was held not liable for executing a writ not bad on the face of it although issued without jurisdiction unless the officer knew of the defect. Moreover, the officer was not required to do more than plead the writ itself, and to allege that it was issued out of an inferior court and was not bad on its face. It would then be up to the plaintiff to show that the officer knew of the defect in jurisdiction. Of course, if the warrant itself is bad in form, the officer executes it would be presumed to know of this and would have no defence.
A private person who irregularly obtains a warrant is not protected in executing it. If the warrant is void, then such a person has no defence. If it is voidable the private individual is protected unless ‘the process has been set aside by reason of some misconduct, or at least some irregularity, on the part of the person suing it out’.
[6.48] Any defendant, whether an official or private individual, who fails to act in accordance with the process will be liable. So, for example, the bailiffs in O’Connor v Sheriff of Queensland and Harvey v Birrell were held liable for seizing goods of persons not named in the writs, the court in the latter remarking that ‘no amount of bona fides on the part of an officer of the Court who made a mistake of this kind could disentile the plaintiff to the damage he had actually sustained’. An official who properly seizes goods but who thereafter disposes of them in an unauthorised way will also be liable. Where a mining plant worth probably £400 was seized pursuant to a writ of fieri facias and sold for £10 in order to satisfy a debt of £116, the sheriff in Smith v Colles was held liable in negligence for proceeding with the sale with what was described as ‘disastrous speed’, leading to the sacrifice of valuable property. By comparison, the sheriff in Anderson v Liddell was held not liable for selling land at a public auction for a price that may have been low but was not illusory or unfair. And in Clarke v Cowper an action in trespass was not maintainable against a sheriff who, acting under writ of habere facias, handed over to a successful plaintiff in an action for ejectment more land than the latter was entitled to; the remedy of the person aggrieved, if any, was by writ of restitution.
Where a warrant is expressed to be valid for a named period only, action taken after it has expired will render the officer liable. This would not, however, preclude a sheriff from taking action to re-arrest an escaped prisoner, provided the initial arrest took place timeously. But a sheriff who thereafter placed the prisoner in gaol on his own responsibility instead of taking him before the court to answer his contempt, as directed by the warrant, was liable in an action for false imprisonment. The courts thus insist on strict adherence to the terms of the process. Similarly, the sheriff in Copeland v Buck, who lodged his prisoner in the Adelaide gaol, despite a request by the latter to be taken before a magistrate and in the face of a warrant which allowed the sheriff to take such a step only if the prisoner did not make such a request, was held liable for false imprisonment.
In general, these rules seem to strike a fair balance between the necessary protection of private rights and the proper security which bailiffs, sheriffs and like ministerial officers require in performing their duties.
 The meaning of ‘judicial process’ was discussed by Hardie Boys J in Simpson v Attorney-General (Baigent’s Case)  1 NZLR 667 at 696. The term was held to include a search warrant regardless of whether it has been validly issued: Auckland Unemployed Workers’ Rights Centr Inc vAattorney-General  3 NZLR 720 at 728 per Hardie Boys J.
 This is sometimes reflected in legislation: see, eg, Supreme Court Act 1933 (ACT) s 50, which sets out the powers and functions of the sheriff.
 Brown v Watson (1871) 23 LT 745
 Williams v Williams and Nathan  2 All ER 559 (CA).
 Ives v Lucas (1823) 1 C & P 7.
 Andrews v Marris (1841) 1 QB 3
 Hooper v Lane (1847) 10 QB 546 at 560-1 (obiter).
 As to the characteristics of a valid search warrant, see R v Sanders  3 NZLR 451.
 See the judgments in the last two cases cited and Denver v Cook (1903) 88 LT 629.
 Andrews v Marris (1841) 1 QB 3.
 (1937) 38 SR (NSW) 85 at 97 per Davison J.
 See London Corporation v Cox (1867) LR 2 HL 239 at 163 per Wiles J (obiter); Watson v Bodell (1845) 14 M & W 57 at 70 per Parke B (ratio); Robertson v Wwestern Australia (1997) 92 A Crim R 115 (WA SC).
 Carrat v Morley (1841) 1 QB 18.
 Painter v Liverpool Oil Gas Light Co (1836) 3 Ad & El 433; Codrington v Lloyd (1838) 8 Ad & El 449.
 Brooks v Hodgkinson (1859) 4 H & N 712.
 Wwilliams v Smith (1863) 14 CB NS 596 at 624 per Willes J.
 (1892) 4 QLJ 213.
 (1878) 12 SALR 58.
 Ibid at 59 (the action was for trespass on premises, seizure and sale).
 And see Simpson v Attorney-General  3 NZLR 667 at 687-8 (wrong address).
 Jelks v Haywood  2 KB 460; cf Donnell;y v Amalgamated Television Services Pty Ltd (1998) 45 NSWLR 570 (unlawful use of video obtained in execution of search warrant).
 (1871) 2 VLR 195.
 (1968) 117 CLR 36.
 (1889) 10 LR (NSW) 106.
 Watson v Bodell (1845) 14 M & W 57.
 Wall v Meyrick (1879) 5 VLR 260. The sheriff may be liable to pay the damages sustained by the person at whose civil suit the prisoner was taken into custody if that prisoner escapes out of custody: see, eg, Supreme Court Act 1986 (Vic) s 120(2).
  SASR 214.