Criminal Law: Necessity

Necessity

Establishing Necessity

Necessity is a complete defence to any offence, and has three elements: Re A (Conjoined Twins) [2001] 2 WLR 480.

  1. The defendant’s actions were necessary to avert an irreparable and inevitable evil;
  2. The defendant did not do more than was reasonably necessary to avert that evil; and
  3. The defendant’s actions and their consequences were not disproportionate to the evil the defendant was trying to avert.
The Evil

It appears that necessity is not available to avert all evils.

The courts have denied that necessity would be available to a homeless person who committed breaking and entering for shelter or theft for food, for example: Southwark London Borough v Williams [1971] 2 All ER 175.

Most successful necessity cases involved a threat to life or potential serious injury. The exception is medical treatment cases, where necessity has successfully been invoked for lesser threats to physical and mental health: Gillick v West Norfolk and Wisbech Area Health Authority [1986] AC 112.

The ‘Selection’ Problem

If the victim died, the defence of necessity only applies if there is no ‘selection problem’: Re A (Conjoined Twins) [2001] 2 WLR 480. A selection problem is where multiple people in the scenario could die, which could be averted by killing any one of them: R v Dudley and Stephens (1884) 14 QBD 273. Necessity only applies if there is no need to select a victim between multiple options, as such. For example:

Scenario 1: Three men are trapped in a boat lost at sea. All three will starve unless they kill and eat one of them. Any of the men are a viable candidate to be the victim. As such, there is a selection problem. The defence of necessity cannot apply.

Scenario 2: The defendant is a mountain climber who is roped to another person. That person slips and falls. They will drag the defendant down with them (killing both) unless the defendant cuts the rope. There is only one option of who to kill to avert the evil, so no selection problem. Necessity is available.

Necessity and Negligence

Necessity is probably not a defence to any offence of negligence. This is because the necessities of the situation are taken into account when determining the offence was committed in the first place: DPP v Harris [1995] 1 Cr App 170. Necessity will affect how a reasonable person would behave, so a necessary action is naturally non-negligent.

Necessity and Strict Liability

Necessity is usually available as a defence to strict liability offences: Santos v CPS [2013] EWHC 550 (Admin). However, a correct interpretation of the statutory provision may lead to the conclusion that Parliament intended to exclude the defence: Cichon v DPP [1994] Crim LR 918.


0%

Criminal Defences Quiz

Test yourself on the principles governing when a defendant has a defence to a criminal charge.

1 / 31

Is the defence of necessity available to an offence of strict liability?

 

2 / 31

Celestine owes a loan shark, Mia, a lot of money. On Sunday night, Mia tells her that if Celestine does not pay her back by Monday morning she will kill her daughter. Celestine tries to get help from the police, but they tell her they do not believe her. Celestine then robs a local corner store to get the money to pay back Mia, but is caught soon after and arrested. Can Mia rely on the defence of duress?

 

3 / 31

Josephine commits a crime involuntarily because of a hyperglycemic episode. Which defence would you advise her to rely on?

4 / 31

Insanity is not a defence to an offence of negligence or strict liability. True or false?

 

5 / 31

Ellen is 17 years old but suffers from a developmental disorder which gives her the emotional maturity of a 7 year-old. Can she escape liability on the grounds that she lacks criminal responsibility?

 

6 / 31

Micah is charged with stealing drugs from a pharmacist. They rely on the defence of duress, arguing that they were under the threat of serious injury or death as they were withdrawing heavily from medication at the time. Is the defence likely to succeed?

 

7 / 31

Can an adult be convicted of being an accessory to a crime committed by a child under the age of criminal responsibility?

 

8 / 31

When establishing self-defence or defence of others, can the defendant rely on any mistaken beliefs as to the circumstances that are the result of his being voluntarily intoxicated?

 

9 / 31

What three elements must be shown to establish the defence of necessity?

10 / 31

Celestine owes her drug dealer, Mia, a lot of money. On Sunday night, Mia tells her that if Celestine does not pay her back by Monday morning she will kill her daughter. Celestine tells her she does not have the money, so Mia tells her to mug Richard as he carries a lot of money on him at all times. Celestine tries to get help from the police, but they tell her they do not believe her. Celestine robs Richard, but is caught soon after and arrested. Can Mia rely on the defence of duress?

 

11 / 31

What are the two elements of the defence of persons defence?

12 / 31

Moira, a teenager, joins a local gang to obtain protection against bullies at school. She knows that the gang have engaged in violent robberies in the past, but the gang leader promises her that they will not involve her in these as she is too young. The gang later threatens to cripple her mother if she does not hold onto a package of drugs for them. Can Moira rely on the defence of duress when charged with drug possession?

 

13 / 31

Lucy, Theo and Marius were trapped in a sinking ship. To buy time pending the arrival of a rescue vessel, Lucy threw Theo overboard. Theo drowned. Lucy has been charged with murdering Theo. She proves that if she did not kill Theo, the ship would have sunk and she and Marius would have died. Can she rely on the defence of necessity?

 

14 / 31

Josephine commits a crime involuntarily because of a hypoglycemic episode. Which defence would you advise her to rely on?

15 / 31

What are the two elements of the defence of insanity?

16 / 31

Can the defence of self-defence be relied on where the force is used pre-emptively?

17 / 31

Can the defence of self-defence be relied on if the defendant provoked the victim to attack?

18 / 31

Is duress a defence to murder?

19 / 31

When determining whether a sober and reasonable person would have succumbed to a duress, what characteristics of the defendant is the hypothetical person given?

20 / 31

Omar takes prescription medicine for depression. One day, he has a rare reaction to the medicine which causes him to involuntarily commit a criminal offence. The prosecution argue that he cannot rely on the defence of automatism, because he voluntarily took the medicine which caused the automatism. Will this argument succeed?

 

21 / 31

Leo is trying to escape a burning building. The only way out is up a ladder, but that ladder is being blocked by Gareth. Gareth is frozen in fear and cannot move out of the way to let Leo pass, nor can he move up the ladder. Because they will both die if Leo does nothing, Leo pulls Gareth off the ladder, causing him to fall to his death. He is later charged with Gareth's murder. Is the defence of necessity available to him?

 

22 / 31

Micah mistakenly believes that Joseph is threatening to kill her unless she robs a bank. Can she rely on her mistaken belief to establish the defence of duress?

23 / 31

Atticus gets extremely drunk at a party, and commits an offence as a result. He claims the alcohol made him act involuntarily, and advances the defence of automatism. Will his defence succeed?

 

24 / 31

What are the three elements of the defence of duress?

25 / 31

Celestine is driving when she feels the onset of a hypoglycemic episode. She is not able to pull over in time before the episode starts. She is barely in control of her body, but is able to move the steering wheel a little and as a result is able to avoid hitting pedestrians. She eventually collides with a tree. Can Celestine rely on the defence of automatism in relation to any criminal offence she is charged with?

26 / 31

What three elements must the defendant show to rely on the defence of automatism?

27 / 31

When establishing the defence of duress, what three elements must exist before the impact of the threat on the defendant is considered sufficient?

28 / 31

People are under a duty to retreat rather than use force in self-defence is they are able. True or false?

 

29 / 31

What is the age of criminal responsibility in England and Wales?

30 / 31

For the purposes of the defence of insanity, a disease of the mind may be caused by any internal or external trigger. True or false?

 

31 / 31

For the purposes of the defence of insanity, a disease of the mind includes mental illnesses and not physical illnesses. True or false?

 

Your score is