However, contrasting to cases involving business parties, the threat to do a lawful act will probably be duress if used against a vulnerable person.
Smith (1994 at p584) commented: ... duress is a unique defence in that it is so much more likely than any other to depend on assertions which are peculiarly difficult for the prosecution to investigate or subsequently to disprove.
This approach has been adopted by the judiciary, most notably by the House of Lords in R v H [2004] 2 WLR 335:[6] Defences that the accused has been set up and allegations of duress, which used to at one time to be rare, have multiplied.
To counter these problems, the Law Commission (1993 at paras 33–34) recommended that the burden of proof be shifted to the defendant to establish duress on the balance of probabilities.
Bingham notes at paragraph 19: The victim of a crime committed under duress may be assumed to be morally innocent, having shown no hostility or aggression towards the defendant.
In the Australian case of R v Hurley & Murray[14] escaped criminals compelled H to dispose of two corpses by holding his wife hostage, such that the threats to her "would have been operative during the entire period of his absence" and "his only concern must have been for the safety of the woman".
In R v Hudson and Taylor,[19] two young women who had witnessed a serious assault were intimidated and refused to identify the attacker in court.
In R v Conway,[24] the Court of Appeal dealt with a charge of reckless driving where the defendant had fled from police officers.
His passenger had recently been attacked by a man with a shotgun, and screamed at the defendant to "drive off" when he saw the plain-clothed officers running toward the car.
The court held that to establish "duress of circumstances", it was necessary for him to drive as he did believing it necessary to avoid death or serious bodily injury to himself or another person.
The requirements were that Thus, in DPP v Bell[26] the accused successfully pleaded duress of circumstances to driving with excess alcohol because, following an incident in a pub which caused him to fear for his physical safety, he escaped in his car, only driving a short distance to safety and then abandoning the criminal activity as soon as reasonably possible.
The action was being taken to defend the child so three defences were raised: The danger must be such that the accused cannot reasonably, taking into account any of their relevant characteristics, be expected to act otherwise.
In R v Pommell[28] the defendant was charged with possession of an illegal firearm, a sub-machine gun, which he claimed to have taken from another person in order to prevent that other from using it and to hand it to the police.
There was some doubt as to how long the weapon had been in his possession, which resulted in his conviction because the jury decided that he had not acted as soon as was reasonable in the circumstances.
The court held that the defence was available as long as the crime was a reasonable and proportionate response to an imminent peril of death or serious injury.
In the earlier case of R v Fitzpatrick,[31] involving the IRA, Lowry LCJ, said at p 33: A person may become associated with a sinister group of men with criminal objectives and coercive methods of ensuring that their lawless enterprises are carried out and thereby voluntarily expose himself to illegal compulsion, whether or not the group is or becomes a proscribed organisation ... if a person voluntarily exposes and submits himself, as the appellant did, to illegal compulsion, he cannot rely on the duress to which he has voluntarily exposed himself as an excuse either in respect of the crimes he commits against his will or in respect of his continued but unwilling association with those capable of exercising upon him the duress which he calls in aid.In cases involving less serious criminality, R v Sharp[32] involved a gang of robbers, while R v Shepherd[33] involved a group of shoplifters, the court held: ... but in my judgment the defence of duress is not available to an accused who voluntarily exposes and submits himself to illegal compulsion.
The Lords in Hasan clearly stated at para 37: Nothing should turn on foresight of the manner in which, in the event, the dominant party chooses to exploit the defendant's subservience.
There need not be foresight of coercion to commit crimes, although it is not easy to envisage circumstances in which a party might be coerced to act lawfully.
Previously, in Director of Public Prosecutions for Northern Ireland v Lynch,[37] the Lords had held by a majority that duress was available to an accomplice.
[40] In Shayler, Lord Woolf remarked obiter that the defence should be extended to include acts designed to protect a person's mental, as well as physical health, from serious injury.