Presumption of mens rea where a statutory offence is silent (B v DPP)
The (fictional) Cash Couriers Act 2025 provides in section 2: 'A person who recruits a person under the age of 18 to carry cash for reward commits an offence', punishable by up to 10 years' imprisonment. The Act says nothing about the defendant's state of mind and contains no other relevant provision. Rhys Morgan is charged with recruiting Danny, aged 17. Rhys says he honestly believed that Danny was 19, although the prosecution argues that his belief was unreasonable because Danny looked young and was in school uniform.
Which of the following best describes the mental element the court is likely to require as to Danny's age?
Choose one answer to see the reasoning.
Worked answer
Correct answer D: The prosecution must prove Rhys did not honestly believe Danny was 18 or over; an honest belief suffices even if unreasonable.
THE RULE TO REMEMBER
Where a statutory offence is silent on mental element, mens rea is presumed unless excluded expressly or by compellingly clear necessary implication; an honest, even unreasonable, mistaken belief negatives it.
Presumption of mens rea where a statutory offence is silent (B v DPP)
In B (A Minor) v DPP [2000] UKHL 13, Lord Nicholls held that where a statutory offence is silent on the mental element, the starting point is the established common law presumption that mens rea is an essential ingredient unless Parliament has indicated a contrary intention expressly or by necessary implication. A necessary implication must be compellingly clear, drawn from the language, the nature of the offence, the mischief and any other relevant circumstances. The more serious the offence, the greater the weight of the presumption. A protective purpose alone does not show that liability was meant to be strict. The House also held that an honest belief negatives mens rea even if unreasonable; reasonableness goes only to whether the belief was genuinely held. Here section 2 creates a serious offence and nothing displaces the presumption, so the prosecution must prove the absence of a genuine belief that Danny was 18 or over.
Why A is wrong: A protective purpose does not by itself create a compellingly clear implication of strict liability, especially for a serious offence.
Why B is wrong: B v DPP held that the 'reasonable grounds' formulation is no longer correct; an honest belief, even if unreasonable, is enough.
Why C is wrong: The burden of proving the mental element rests on the prosecution in the usual way; the defendant does not have to prove his belief.
Why E is wrong: The presumption is a rule of statutory interpretation that applies to every statutory offence that is silent as to mens rea.
A little more practice done.
Related questions
Using Hansard to interpret a statute: the conditions in Pepper v Hart [1993] AC 593
Which of the following best describes the extent to which the court may consider this Parliamentary material?
Using explanatory notes and Law Commission reports as aids to interpretation (R (O) v SSHD)
Which of the following best describes the use the court may make of these documents?
Purposive interpretation and developments Parliament did not foresee (Quintavalle)
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