Nabieu Amadu v. Aiah Sidiki (Privy Council App. No. 14/69) – [1973] SLHC 3

• Illegality and bailment – If possession of certain goods is prohibited by statute, any bailment of those goods is unenforceable. A party cannot rely on illegal possession to claim return of the goods or their value.

• Ex turpi causa – Courts will not lend their aid to a plaintiff who must rely on an illegal act to establish his claim. A claim based on illegal possession of a diamond cannot be enforced.

• Pleading illegality – Failure to plead the defence of illegality is immaterial where the illegality is at the root of the plaintiff’s claim. Only where the illegality arises from surrounding circumstances must it be specifically pleaded so the plaintiff has adequate warning.

• Minerals Act of Sierra Leone – Sections 66–68 require a licence or mining right to possess diamonds. Possession of a diamond without authorisation is unlawful.

Procedural Posture

The case arose from a dispute over a valuable diamond. The plaintiff, Nabieu Amadu, claimed that he found a “gem stone” by the roadside and delivered it to his guardian, Aiah Sidiki, for safekeeping. Sidiki allegedly sold the stone for £44,000 but refused to hand over the proceeds. Amadu sued in the then Supreme Court of Sierra Leone seeking return of the stone or its value. The trial judge accepted Amadu’s evidence, disbelieved the defence and awarded him the value of £44,000.

On appeal to the Court of Appeal the defendant argued, for the first time, that the transaction was illegal because possession and dealing in diamonds without a licence contravened the Minerals Act (Cap. 196). The Court of Appeal upheld the trial judge’s findings of fact but held that the transaction was illegal and unenforceable. It allowed the appeal and ordered that the proceeds of sale in the defendant’s bank accounts be paid to the Crown. Both parties appealed to the Judicial Committee of the Privy Council. The appeals were consolidated, although the defendant ultimately chose not to prosecute his appeal. The Privy Council was asked to determine whether the failure to plead illegality should affect the outcome and whether the courts could enforce the bailment notwithstanding the illegality.

The report also contains a brief criminal appeal involving the same parties. In that matter the Privy Council upheld the conviction but reduced the sentence to seven years’ imprisonment. Since details of the offence are not given, this report focuses on the civil bailment appeal.

Facts of the Case

• Discovery of a stone – In February 1966 the plaintiff said he found a piece of gem stone while walking in a diamond‑mining district of Kono, Sierra Leone. He entrusted it to his guardian, the defendant, for safekeeping. The defendant later admitted to several village elders, including the Paramount Chief, that he had sold the stone for £44,000 but did not account to the plaintiff.

• Action in the Supreme Court – The plaintiff sued for the return of the stone or its value, claiming that the defendant was his bailee. The defence was a bare denial. At trial the plaintiff and three witnesses testified that Sidiki had admitted selling the stone and depositing the proceeds in bank accounts. The defendant denied ever receiving a stone. The trial judge believed the plaintiff and entered judgment in his favour for the return of the stone or £44,000.

• New defence on appeal – On appeal the defendant argued for the first time that the transaction was illegal because, under sections 66–68 of the Minerals Act, it is unlawful to possess or deal in diamonds without a mining lease, prospecting licence or purchase licence. The Court of Appeal agreed that the stone was a diamond, that the plaintiff possessed it unlawfully and that the courts could not enforce a claim founded on illegal possession. It ordered the proceeds to be paid to the Crown.

• Cross‑appeals to the Privy Council – Both parties appealed. The plaintiff challenged the finding of illegality and the order directing the proceeds to the Crown. The defendant lodged a cross‑appeal but ultimately did not pursue it. The Privy Council consolidated the appeals and considered whether illegality must be pleaded and whether the courts should enforce the transaction despite the illegality.

Issues for Determination

1. Whether the courts can enforce a bailment when possession of the subject‑matter (a diamond) is illegal under the Minerals Act.

2. Whether failure to plead the defence of illegality should prevent the court from taking notice of illegality that is at the root of the plaintiff’s claim.

3. Whether the Court of Appeal was correct to direct that the proceeds of sale of the diamond be paid over to the Crown.

Arguments of the Parties

Plaintiff’s Submissions (Appellant)

• Good title and bailment – The plaintiff contended that he had lawfully acquired a “gem stone” by finding it on the road and that he delivered it to the defendant as bailee. He argued that the defendant had sold the stone and wrongfully retained the proceeds. The plaintiff maintained that the Court of Appeal erred in finding the transaction illegal because no illegality had been pleaded or proven.

• Failure to plead illegality – Counsel argued that, even if the Minerals Act applied, the defence of illegality should have been specifically pleaded. It was unfair to allow the defendant to raise illegality for the first time on appeal, depriving the plaintiff of the opportunity to rebut the issue.

Defendant’s Submissions (Respondent)

• Illegality at the root of the claim – The defendant (represented by senior counsel before the Privy Council, though ultimately not pressing the appeal) argued that the plaintiff’s claim was based on his own illegal possession of a diamond. Under the Minerals Act, only licence holders or mining right holders may possess or trade in diamonds. Since the plaintiff found the diamond and retained it without a licence, his possession was unlawful. The common‑law maxim ex turpi causa non oritur actio bars the court from assisting a plaintiff who relies on his own illegal act.

• Pleaded or not, illegality barred relief – The respondent contended that where illegality is intrinsic to the claim, it is immaterial that it was not pleaded or argued below. The court must refuse to enforce an illegal transaction on grounds of public policy. The defendant also maintained that the proceeds of sale properly belonged to the Crown under the Minerals Act.

Authorities Cited

• Minerals Act (Cap. 196) of Sierra Leone – Sections 66–68 and 71 require a licence to possess or purchase minerals and criminalise unauthorised possession. The Act was applied to diamonds by order of the Governor in Council. Section 67 prohibits possession of minerals without a mining lease, prospecting licence or purchase licence; section 68 makes possession without proof of lawful acquisition an offence; section 71 empowers the Governor to issue purchase licences. These provisions underpinned the finding that the plaintiff’s possession of the diamond was illegal.

• North Western Salt Co. Ltd. v. Electrolytic Alkali Co. Ltd. ([1914] A.C. 461) – Cited for the proposition that failure to plead illegality is inconsequential where the illegality is intrinsic to the plaintiff’s claim. A court will not enforce an illegal contract or transaction, even if the defendant did not plead the defence.

• Holman v. Johnson (1775) – Lord Mansfield famously observed that “no court will lend its aid to a man who founds his cause of action upon an immoral or an illegal act.” This maxim underpins the illegality doctrine and was referenced in commentary on this caselegal500.com.

• Tinsley v. Milligan ([1994] 1 A.C. 340) and Patel v. Mirza ([2016] UKSC 42) – Modern cases illustrating the evolution of the illegality defence. In Tinsley, the House of Lords adopted a strict reliance test, holding that if the claimant must rely on an illegal act to establish her case, the claim fails. In Patel, the Supreme Court replaced the reliance test with a discretionary balancing approach, considering the policy behind the prohibition and whether denying relief would be disproportionatelegal500.com.

Decision / Judgment

Delivering the advice of the Board, Lord Salmon dismissed both appeals. The Privy Council held that the Court of Appeal was right to set aside the trial judgment and refuse to enforce the plaintiff’s claim for the return of the diamond or the proceeds. The key points of the judgment were as follows:

• Unlawful possession of a diamond – Evidence at trial, including admissions made by the defendant to witnesses, established that the stone found by the plaintiff was a diamond worth £44,000. Under the Minerals Act, possession of a diamond without a licence is illegal. The plaintiff was therefore in unlawful possession and could not invoke the court’s assistance to recover the diamond or its value. The court noted that both parties were careful at trial to describe the stone merely as a “gem stone,” but the plaintiff’s own witness inadvertently revealed that it was a diamond.

• Ex turpi causa bars relief – The plaintiff’s claim was “a blatant attempt to enforce an illegal transaction.” The Privy Council reaffirmed that courts will not enforce a claim that is rooted in illegality. Since the plaintiff’s cause of action relied on his illegal possession of the diamond, his claim was barred.

• Pleading illegality unnecessary – Because the illegality was at the root of the claim, it was irrelevant that the defence of illegality was not pleaded or argued at trial. The public policy of preventing the courts from enforcing illegal transactions overrides procedural niceties. The situation would be different if the illegality arose from collateral circumstances not integral to the plaintiff’s cause of action. In such cases, illegality should be pleaded so that the claimant has notice and can address it.

• Order for proceeds to be paid to the Crown – The Court of Appeal had ordered that the proceeds of sale be paid to the Crown. The Privy Council upheld that order, noting that diamonds are the property of the Crown under the Minerals Act and that illegally obtained diamonds and their proceeds revert to the state. Consequently, the plaintiff recovered nothing, and the defendant’s proceeds were confiscated.

• Dismissal of consolidated appeals – Both appeals were dismissed. The defendant’s cross‑appeal was not pursued; the Board therefore confirmed the Court of Appeal’s disposition.

Key Quotations from the Judgment

Illegality at the root of the claim: “Their lordships are of the opinion that the Court of Appeal were clearly right in allowing the appeal and dismissing the plaintiff’s action on the ground that the plaintiff’s claim could not properly be entertained by the courts since it was a blatant attempt to enforce an illegal transaction.”

No need to plead illegality when intrinsic: “In these circumstances, the fact that illegality was not pleaded nor argued at the trial is of no consequence.”

Unlawful possession under the Minerals Act: After citing sections 67–68, the Board noted that “if the stone which the plaintiff said he found in the road and took into his possession was a diamond, he was clearly in unlawful possession of it in breach of s. 67.”

Ratio Decidendi

The central principle of the decision is that where a plaintiff’s claim is founded upon his own illegal possession of property, the courts will not enforce the claim. Possession of a diamond without statutory authority under the Minerals Act rendered the bailment illegal. Consequently, the bailor could not recover the diamond or its value from the bailee. It is immaterial that the defence of illegality was not pleaded; when illegality is intrinsic to the claim, the court must refuse relief on public policy grounds. Only if the illegality arises incidentally from surrounding circumstances must it be specifically pleaded.

Obiter Dictum

The Board observed that if illegality is not at the root of the claim but arises only from surrounding circumstances, it must be pleaded so that the plaintiff has adequate notice and an opportunity to respond. This comment clarifies the procedural requirements for raising a defence of illegality and serves as a caution to practitioners. It did not affect the outcome because the plaintiff’s illegal possession was integral to his claim.

Final Orders / Reliefs Granted

1. Appeal dismissed – The plaintiff’s appeal was dismissed. The judgment of the Court of Appeal (which set aside the trial court’s order) was affirmed.

2. Proceeds forfeited to the Crown – The order directing that the proceeds of sale of the diamond be paid over to the Crown was upheld.

3. Cross‑appeal dismissed – The defendant’s cross‑appeal was dismissed as it was not pursued. The sentence reduction in the criminal matter (seven years’ imprisonment) stands but is not further elaborated.

Commentary / Practice Note

A. Illegality and Bailment

This case is a striking illustration of the principle ex turpi causa non oritur actio (“no action arises from a base cause”). Although framed as a bailment, the plaintiff’s claim depended on his own illegal possession of a diamond. The Privy Council reaffirmed that courts will not enforce a transaction that contravenes statutory prohibitions, even if the defendant never pleaded illegality. Practitioners should advise clients that if they cannot show lawful title to goods whose possession is regulated (such as minerals or contraband), they will be unable to recover them through the courts.

B. Pleading Illegality

The decision clarifies when illegality must be specifically pleaded. If the illegality is intrinsic to the plaintiff’s claim, the court may take notice of it at any stage because enforcing the claim would undermine public policy. In such cases, failure to plead illegality does not cure the defect. By contrast, if the illegality arises only from surrounding circumstances not relied on by the plaintiff (for example, where the contract is lawful on its face but collateral facts render performance illegal), the defence must be pleaded to give the claimant an opportunity to meet it. This distinction stems from cases such as North Western Salt Co. v. Electrolytic Alkali Co. and remains good law.

C. Evolution of the Illegality Doctrine

The case predates the modern re‑examination of the illegality doctrine. In Tinsley v. Milligan, the House of Lords adopted a rigid “reliance” test: a claimant is barred if she must rely on an illegal act to make her claim. The later Supreme Court decision in Patel v. Mirza rejected the reliance test and endorsed a more flexible, discretionary approach, balancing the purpose of the prohibition, the public interest and proportionalitylegal500.com. Under Patel, courts may enforce a claim even if it involves illegality, provided doing so would not stultify the policy underlying the prohibition and would prevent unjust enrichment. Had Patel been applied, a court might have considered whether denying relief to the finder of a diamond unduly benefits an unscrupulous bailee. Nevertheless, the statutory framework in Sierra Leone and the strong public policy against unauthorised possession of minerals likely still require forfeiture of illegally obtained diamonds to the state.

D. Practical Implications

1. Due diligence in mineral‑rich areas – Individuals who find or trade in minerals must obtain the requisite licences under the Minerals Act. Failure to comply will not only expose them to criminal liability but will also bar them from enforcing any bailment or sale of the mineral. The goods and any proceeds may be forfeited to the Crown.

2. Advising bailees and trustees – Those entrusted with valuable property should ensure that the bailor has legal title. Accepting and dealing with contraband exposes the bailee to criminal sanctions, forfeiture and potential liability to the Crown.

3. Drafting pleadings – Defence counsel should plead illegality when it arises from surrounding circumstances, but need not do so where the claim is obviously illegal on its face. Plaintiffs should be prepared to address possible illegality issues, especially in cases involving regulated goods.

4. Law reform – The case highlights the tension between rigid application of the illegality doctrine and equitable considerations. Modern courts have moved towards a discretionary approach. Legislatures and courts in Sierra Leone may consider adopting a balancing test similar to Patel v. Mirza to ensure that the illegality defence does not produce disproportionate outcomes.

Tags and Categories (for Lanbuk.com indexing)

Categories: Bailment and Conversion; Property Law; Public Policy and Illegality; Mineral and Mining Law; Civil Procedure.
Tags: bailment, diamond, illegal possession, ex turpi causa, minerals act, pleading, forfeiture, public policy, illegality defence.

Objective (Multiple‑Choice) Questions

1. Under the Minerals Act of Sierra Leone, who may lawfully possess a diamond?

A. Anyone who finds it by chance.
B. Only a lessee of a mining lease, holder of a mining right or prospecting licence, or a licensee authorised to purchase minerals.
C. Any person who is over 18 years old.
D. Any bailee who acts honestly.

2. Why did the Privy Council refuse to enforce the plaintiff’s claim for the return of the diamond or its value?

A. Because the plaintiff had not proved the value of the diamond.
B. Because the defendant denied receiving the diamond.
C. Because the plaintiff’s claim relied on his illegal possession of a diamond, and courts will not enforce an illegal transaction.
D. Because the trial judge misdirected the jury.

3. In the context of this case, what is the significance of failing to plead the defence of illegality?

A. It prevents the defendant from raising illegality at any stage.
B. It is irrelevant when the illegality is intrinsic to the plaintiff’s claim and the court must refuse relief on public policy grounds.
C. It automatically gives the plaintiff a right to damages.
D. It allows the plaintiff to recover the proceeds of sale.

4. Which of the following statements best captures the ratio decidendi of Nabieu Amadu v. Aiah Sidiki?

A. Courts will assist a finder of a diamond to recover it from a dishonest bailee.
B. Courts will not enforce a bailment where the subject‑matter is possessed illegally; illegality at the root of the claim bars relief irrespective of pleading.
C. All defences must be pleaded or are deemed waived.
D. Criminal sentences may be reduced on appeal.

5. The decision in North Western Salt Co. v. Electrolytic Alkali Co. was cited to illustrate which procedural principle?

A. That contracts in restraint of trade are void.
B. That failure to plead illegality is immaterial when the illegality is integral to the claim.
C. That damages must be assessed equitably.
D. That a criminal conviction is not relevant in civil proceedings.

6. Which modern case replaced the strict reliance test for illegality with a discretionary balancing approach?

A. Holman v. Johnson.
B. North Western Salt Co. v. Electrolytic Alkali Co.
C. Tinsley v. Milligan.
D. Patel v. Mirza.

7. What happened to the proceeds of the sale of the diamond under the Court of Appeal’s order affirmed by the Privy Council?

A. They were returned to the plaintiff.
B. They were kept by the defendant.
C. They were paid over to the Crown as required by the Minerals Act.
D. They were shared equally between the parties.

8. Which of the following best describes the proper approach to pleading illegality when the illegality arises from surrounding circumstances and not at the root of the claim?

A. It need not be pleaded because the court can take judicial notice.
B. It must be specifically pleaded to give the plaintiff adequate warning.
C. It is raised automatically on appeal.
D. It cannot be raised in civil proceedings.

9. The maxim “ex turpi causa non oritur actio” means:

A. A bad cause of action may still succeed if pleaded correctly.
B. Courts will not assist a claimant who must rely on his own illegal act.
C. Equity will always intervene to prevent injustice.
D. The criminal law does not affect civil claims.

10. How has the approach to the illegality defence evolved since Nabieu Amadu v. Aiah Sidiki?

A. It has become more rigid, with courts refusing relief whenever illegality is present.
B. It has shifted towards a balancing test, considering the purpose of the prohibition and proportionality, as exemplified by Patel v. Mirza.
C. It has been abolished by statute.
D. It remains unchanged and strictly applied as in 1973.

Answers to Objective Questions

1. B; 2. C; 3. B; 4. B; 5. B; 6. D; 7. C; 8. B; 9. B; 10. B.

Essay Questions

1. Analyse the decision in Nabieu Amadu v. Aiah Sidiki within the context of the illegality doctrine. How does the court’s reasoning reflect the classical view of ex turpi causa non oritur actio, and how might the outcome differ if the modern approach in Patel v. Mirza were applied?

Answer: The Privy Council’s reasoning is rooted firmly in the traditional illegality doctrine. It refused to lend its aid to a plaintiff whose cause of action rested on his own illegal possession of a diamond, quoting Lord Mansfield’s maxim that no court will assist a man who founds his claim on an immoral or illegal actlegal500.com. Because the plaintiff’s bailment claim relied on an act prohibited by statute (possession of a diamond without a licence), the court held that public policy required dismissal of the action regardless of whether illegality was pleaded. This strict approach treats illegality as a jurisdictional bar: once the court identifies that the claim is tainted, it declines to engage with the merits.

By contrast, Patel v. Mirza introduced a discretionary balancing test, asking whether enforcing the claim would undermine the purpose of the prohibition, whether denying relief would be a proportionate response, and whether there would be a disproportionate windfall to one partylegal500.com. Applying this modern approach, a court might consider factors such as: (1) the statutory purpose of the Minerals Act in preventing unlicensed mining and smuggling of diamonds; (2) the conduct and relative culpability of the plaintiff and defendant; and (3) whether denying relief would unduly enrich the defendant at the plaintiff’s expense. The plaintiff found a diamond but may have had no intention of illegally trafficking it; the defendant, as guardian, arguably took advantage by selling it and pocketing the proceeds. A balancing approach could lead to an outcome that, while punishing the illegality by forfeiting the diamond to the Crown, allows the plaintiff to recover the value of his labour or to prevent unjust enrichment of the bailee. Thus, the outcome might differ, but the strong public policy against unauthorised possession of minerals could still tilt the balance towards forfeiture.

2. Discuss the distinction between intrinsic illegality and collateral illegality as articulated in the judgment. Why is this distinction important in civil litigation, and how should lawyers frame pleadings in light of it?

Answer: The judgment differentiates between intrinsic illegality—where the illegal act constitutes the very foundation of the plaintiff’s claim—and collateral illegality, where the illegal act arises from surrounding circumstances that do not directly underpin the cause of action. In Nabieu Amadu v. Aiah Sidiki, possession of the diamond was intrinsically illegal; the claim sought to enforce a bailment of contraband. Since enforcing the bailment would legitimise an illegal act, the court refused relief even though the defence of illegality was not pleaded.

Collateral illegality, by contrast, refers to situations where the contract or transaction is lawful on its face but performance or some peripheral aspect involves illegality. In such cases, the illegality must be specifically pleaded and proven because it does not automatically taint the underlying claim. This ensures procedural fairness by giving the plaintiff notice and an opportunity to respond. The distinction is important because it affects whether courts can take notice of illegality on their own motion and whether failure to plead illegality is fatal.

Lawyers should therefore analyse whether alleged illegality is intrinsic or collateral. When representing defendants, they should plead illegality if it arises from surrounding circumstances but may rely on the court’s inherent jurisdiction when the claim is manifestly illegal. Plaintiffs, conversely, should anticipate potential illegality defences and address them in the pleadings, especially in areas subject to statutory regulation.

3. How does the decision illustrate the interaction between common‑law principles (such as bailment and ex turpi causa) and statutory regimes (like the Minerals Act)? Provide examples of how statutory provisions can override or modify common‑law rules.

Answer: The case demonstrates that statutory regimes can fundamentally alter common‑law principles. At common law, bailment allows a bailee to recover goods from a third party or to enforce obligations against a bailee who misuses the goods. However, where possession of the goods is prohibited by statute, the bailment is void and unenforceable. In this case, sections 67–68 of the Minerals Act made possession of a diamond without a licence an offence. This statutory prohibition overrode the common‑law right to maintain an action in bailment. The plaintiff’s claim collapsed because the subject‑matter of the bailment could not be lawfully possessed.

Statutes often modify the common law in other contexts. For instance, the Sale of Goods (Amendment) Act 1994 abolished the doctrine of market overt in English law, removing a common‑law exception to the nemo dat rule. Consumer credit statutes grant innocent purchasers protection against outstanding finance interests, modifying the strict common‑law position that a seller cannot pass better title than he has. Similarly, environmental regulations can prohibit the possession and trade of certain species, rendering any bailment or sale of those goods illegal. Lawyers must therefore be alert to statutory provisions that supersede or qualify common‑law doctrines.

4. Consider the ethical and policy considerations underlying the decision to confiscate the proceeds of sale and pay them to the Crown. Do you agree with this outcome? What alternative remedies might have been considered?

Answer: Confiscating the proceeds of sale and paying them to the Crown reflects the policy of deterring illegal mining and smuggling of diamonds. Allowing either party to retain the proceeds would encourage law‑breaking and undermines the regulatory regime. The plaintiff obtained possession of the diamond illegally, and the defendant, as guardian, exploited the situation for personal gain. Forfeiture sends a clear message that profits derived from illegal acts will not be tolerated and removes the incentive to engage in such transactions.

Some may criticise the outcome as unduly harsh on the plaintiff, who may have innocently found the diamond. Alternatives might include awarding the plaintiff a finder’s reward or allowing him to share in the proceeds after paying a penalty or obtaining a licence retrospectively. Another approach, as suggested by modern cases like Patel v. Mirza, is to balance the deterrent effect against the risk of unjust enrichment. For example, the court could order the defendant to disgorge profits to the state while awarding the plaintiff compensation for his labour or for reporting the discovery. However, the statutory framework in Sierra Leone vests ownership of minerals in the Crown and leaves little room for equitable sharing. Ultimately, whether one agrees with the outcome depends on one’s view of the appropriate balance between deterrence, fairness and public policy.

5. Compare and contrast Nabieu Amadu v. Aiah Sidiki with modern cases dealing with illegal contracts. How has the law’s approach to illegality evolved, and what guidance do these cases provide to practitioners?

Answer: In Nabieu Amadu v. Aiah Sidiki, the Privy Council applied a strict rule: a claim based on illegality will be dismissed, irrespective of pleading, because public policy precludes courts from assisting those who rely on their own unlawful acts. This reflects the classical approach seen in Holman v. Johnson and many nineteenth‑ and early twentieth‑century cases.

Modern jurisprudence has softened this rigidity. Tinsley v. Milligan introduced the reliance test: a claimant is barred if she must rely on the illegality to prove her claim but may succeed if she can establish her case without invoking the illegal transaction. The Supreme Court’s decision in Patel v. Mirza went further, replacing the reliance test with a multifactorial balancing approach. Courts now consider the underlying purpose of the prohibition, other relevant public policy factors and whether denying relief would be proportionate to the illegality. This allows for more nuanced outcomes and avoids windfalls to wrongdoers.

For practitioners, these cases highlight the importance of identifying the statutory and common‑law policies engaged, assessing whether the claimant’s cause of action is tainted by illegality, and framing the case to avoid reliance on illegal acts. In jurisdictions where the law has evolved, counsel should argue for a balanced approach that considers fairness and proportionality, especially where the defendant’s conduct is more culpable than the plaintiff’s.

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