Conspiracy in Nigerian Criminal Law: When Agreement Becomes a Crime
Understanding the Inchoate Offence That Makes Planning a Crime Even Before Action
What if three people sit in a room and agree to rob a bank—but never actually rob it? Can they be prosecuted? What if they’re arrested while planning, before anyone picks up a weapon?
The answer is yes, through the offence of conspiracy. Nigerian law recognizes that when multiple people agree to commit a crime, they become more dangerous than individuals acting alone. The law doesn’t wait for them to execute their plan—the agreement itself is a crime.
This comprehensive guide explains conspiracy under Nigerian law—how it’s defined under both the Criminal Code (Southern Nigeria) and the Penal Code (Northern Nigeria), what prosecutors must prove, and why courts call it “the darling of the prosecutor.”
1. What Is Conspiracy? The Basic Concept
The Simple Definition
Conspiracy is an agreement between two or more people to commit a crime or to do a legal act by illegal means.[^4][^5]
It’s not the crime itself—it’s the agreement to commit the crime.
A “Distinct Evil”
The Supreme Court in Balogun v. AG Ogun State (2002) held that the law treats the act of agreeing to commit a crime as a “distinct evil” from the crime itself.[^4]
What This Means:
- The agreement is itself harmful and punishable
- Even if the planned crime never happens
- Even if the conspiracy fails
Dual Liability
Because conspiracy is a separate offence, you can be charged with:
- Conspiracy to commit the crime, AND
- The substantive crime itself (if it’s actually committed)
Example: Adebayo, Chika, and Emeka agree to rob a bank (conspiracy). They actually rob the bank (robbery). They can be charged with:
- Conspiracy to commit armed robbery, AND
- Armed robbery
2. Why Is Conspiracy Dangerous? The Rationale
Courts and scholars recognize that group criminality is more dangerous than individual criminality for several reasons:[^4][^5]
Reason 1: Enhanced Capability
Multiple people can:
- Divide roles (lookout, driver, actual robber)
- Share expertise (one knows security, another knows safes)
- Overcome obstacles that would stop one person
Reason 2: Emboldening Effect
People in groups are braver. You might hesitate to rob a bank alone, but peer pressure and shared responsibility can push you forward.
Reason 3: Greater Harm Potential
Organized groups cause more damage than individuals. Compare:
- One person stealing a car (individual theft)
- An organized car theft ring (conspiracy + multiple thefts)
Reason 4: Law Enforcement Efficiency
By criminalizing the agreement, the law can intervene early—during planning—rather than waiting for harm to occur.
3. Nigeria’s Dual Legal System: Two Different Laws on Conspiracy
Nigeria has two criminal codes operating in different regions:
| Region | Applicable Law | Key Sections |
|---|---|---|
| Southern Nigeria | Criminal Code | Sections 516-518[^4] |
| Northern Nigeria | Penal Code | Section 96[^5] |
This creates some differences in how conspiracy is defined and prosecuted.
4. Conspiracy Under the Criminal Code (Southern Nigeria)
The Statutory Framework
Sections 516-518 of the Criminal Code govern conspiracy in Southern Nigeria.
Section 516: Conspiracy to Commit Felony
Any person who conspires with another to commit any felony or to do any act in any part of the world which if done in Nigeria would be a felony… is guilty of a felony and is liable to imprisonment for seven years or, if the maximum punishment for that felony is less, then to the maximum punishment.[^4]
Key Points:
- Applies to conspiracy to commit felonies (serious crimes)
- Punishment: 7 years imprisonment (or less if the substantive offence carries less)
- Applies even if the planned crime would occur outside Nigeria
Section 517: Conspiracy to Commit Misdemeanor
Conspiring to commit a misdemeanor (less serious crime) is liable to two years imprisonment.[^5]
Section 518: Other Unlawful Acts
Section 518 covers conspiracies to commit various other acts that may not be felonies or misdemeanors but are still unlawful.
The Unusual Absence of Definition
Unlike the Penal Code, the Criminal Code does not explicitly define conspiracy.[^4]
Instead, Nigerian courts rely on the common law definition from the English case Mulcahy v. R (1868), as adopted in Majekodunmi v. R:[^5]
“A conspiracy consists not simply of the intention of two or more, but of the agreement of two or more to perform an unlawful act or to do an unlawful act.”
What This Emphasizes:
- It’s not enough for two people to separately want to commit a crime
- They must agree to do it together
- The agreement is the crime
5. Conspiracy Under the Penal Code (Northern Nigeria)
Section 96: The Definition
Section 96 of the Penal Code explicitly defines conspiracy (unlike the Criminal Code):[^5]
“When two or more persons agree to do or cause to be done: (a) an illegal act, or (b) an act which is not illegal by illegal means, such an agreement is designated a criminal conspiracy.”
This mirrors Section 120A of the Indian Penal Code.[^5]
The Critical Overt Act Requirement
The Penal Code has a unique requirement not found in the Criminal Code:
When Agreement Alone Is Sufficient
If the agreement is to commit an offence, the agreement alone constitutes conspiracy.[^5]
Example: Bello and Ibrahim agree to murder Yusuf. The agreement itself is conspiracy—no further act needed.
When an Overt Act Is Required
If the agreement is to commit an act that is not an offence (but is merely unlawful), then an overt act besides the agreement must be done by one or more conspirators.[^5]
Example: Two people agree to trespass on land (trespass isn’t a criminal offence, but it’s unlawful). The agreement alone isn’t enough—someone must actually trespass for conspiracy to be established.
Section 97B: Membership in Unlawful Organization
Section 97B provides an additional mechanism for prosecuting group criminality:
Membership in an unlawful organization is punishable with up to seven years imprisonment.[^5]
This helps prosecute conspirators even when proving a specific agreement is difficult.
6. The Five Essential Elements of Conspiracy
Based on Nigerian case law and the statutory provisions, five elements must be proven for conspiracy:[^4]
Element 1: An Agreement
The Core Requirement: There must be a “concurrence and a combination.”[^4]
How Agreement Is Proven
Conspiracy is “rarely capable of direct proof.”[^4] You won’t usually find a written contract saying “We agree to rob this bank.”
Instead, agreement is inferred from circumstances:[^4]
- Coordinated actions
- Communications between parties
- Shared goals
- Division of roles
Case Law: Olusola Oyeleye v. The State established that agreement can be inferred from conduct.[^4]
Example:
- No written agreement exists
- But: All three defendants arrive at the crime scene at the same time
- They each perform different roles (lookout, driver, actual robber)
- They flee together
- Inference: They agreed to work together
Element 2: Two or More People
The Rule: Conspiracy requires at least two people.[^4]
Case Law: Njovens v. State confirmed this requirement.[^4]
You Cannot Conspire Alone
Why? The danger of conspiracy lies in group action. One person planning a crime isn’t a conspiracy—it’s just preparation (or attempt, if they act on it).
Example:
- ❌ Adamu plans to rob a bank by himself → Not conspiracy
- ✅ Adamu and Chidi plan to rob a bank together → Conspiracy
Element 3: Illegal Purpose
The Rule: The goal must be to effect illegality or use unlawful means.[^4]
This can be:
- Committing a crime (felony or misdemeanor)
- Doing a legal act by illegal means
- Doing an act that is unlawful (even if not criminal)
Examples:
- ✅ Agreeing to steal a car (crime)
- ✅ Agreeing to win a contract by bribing officials (legal goal, illegal means)
- ✅ Agreeing to trespass on land (unlawful but not necessarily criminal)
Element 4: Criminal Intent
The Rule: The agreement must be entered for the purpose of committing a crime.[^4]
Case Law: Kenneth Clark v. State established this requirement.[^4]
Distinguishing Innocent Agreements
Not every agreement that coincidentally helps a crime is conspiracy.
Example 1 – NOT Conspiracy:
- Taiwo agrees to drive Bola to a location
- Unknown to Taiwo, Bola plans to rob someone there
- Taiwo has no knowledge of or intent toward the crime
- Result: No conspiracy (Taiwo lacks criminal intent)
Example 2 – IS Conspiracy:
- Taiwo agrees to drive Bola to rob someone
- Taiwo knows the purpose
- Taiwo agrees to the plan
- Result: Conspiracy (both have criminal intent)
Element 5: Inference from Circumstances
The Rule: Since direct proof is rare, conspiracy is “deduced from the acts of the parties directed toward a common purpose.”[^4]
Case Law: Njovens v. State established this.[^4]
What Courts Look For
Courts infer conspiracy from:
- Coordination: Do the defendants’ actions fit together like puzzle pieces?
- Communication: Did they meet, call, or message before the crime?
- Shared knowledge: Did they all know the plan?
- Division of labor: Did each person have a specific role?
- Joint benefit: Would all benefit from the crime?
- Timing: Did they arrive/act at coordinated times?
Example Case Analysis:
Facts:
- Bank robbery occurs at 3pm
- Defendant A parks getaway car at 2:50pm
- Defendant B enters bank with weapon at 2:58pm
- Defendant C blocks rear exit at 2:55pm
- All three flee together at 3:05pm
- They meet at Defendant A’s house later
Inference: Clear conspiracy
- Coordinated timing
- Complementary roles
- Joint flight
- Meeting afterward (to divide proceeds?)
7. The “Bilateral vs. Unilateral” Debate
This is a complex theoretical issue in conspiracy law.
The Bilateral Approach (Rule of Consistency)
The Traditional Common Law Rule: Conspiracy requires two guilty minds.[^4]
The Logical Problem
If A and B are charged with conspiring with each other, and A is acquitted, then B must also be acquitted.
Why? Because the charge says they conspired “with each other.” If A didn’t conspire, then B couldn’t have conspired with A—you can’t conspire with someone who isn’t conspiring.[^4]
Example:
- A and B charged with conspiring together to rob a bank
- At trial, A is acquitted (found not guilty)
- Result under bilateral approach: B must also be acquitted
- Logic: A “man cannot conspire with himself or an innocent party”[^4]
The Unilateral Approach
The Modern Alternative (adopted in American Model Penal Code): Conspiracy requires only one guilty mind.[^4]
How This Works
If A agrees to commit a crime with B, A is guilty of conspiracy even if:
- B is actually an undercover police officer
- B has no criminal intent
- B is merely pretending to agree
Example:
- Ojo approaches an undercover cop and says “Let’s rob that bank together”
- The cop pretends to agree (to gather evidence)
- Result under unilateral approach: Ojo is guilty of conspiracy
- Logic: Ojo agreed to commit a crime with someone—that’s what makes him dangerous
The Nigerian Position
Current Status: Nigeria generally follows the principle that at least two people are needed for conspiracy.[^4]
However, there is “no consensus” on whether the strict bilateral requirement (Rule of Consistency) applies in all contexts.[^4]
Practical Impact:
- If charged together and one defendant is acquitted, the other may also have to be acquitted
- But if charged separately or if there’s a third party involved, the Rule of Consistency may not apply
8. The Husband and Wife Exception
The Common Law Fiction
Under traditional common law, husband and wife are considered “one person” in law.
Since conspiracy requires two people, a “single person” cannot conspire with themselves.[^5]
Section 34 of the Criminal Code
This principle is codified:
“A husband and wife of a Christian marriage are not criminally responsible for a conspiracy between themselves alone.“[^5]
Key Limitations:
- Christian marriage only: This applies only to marriages under the Marriage Act (Christian marriage), not customary or Islamic marriages[^4]
- Conspiracy “alone”: If they conspire with a third party, they are liable
Case Law: Keshiro v. IGP confirmed this exception.[^5]
Examples
Scenario 1 – Exception Applies:
- Mr. and Mrs. Okonkwo (Christian marriage) agree to forge documents
- Just the two of them, no one else involved
- Result: No conspiracy (protected by Section 34)
Scenario 2 – Exception Does NOT Apply:
- Mr. and Mrs. Okonkwo (Christian marriage) agree with their son to forge documents
- Three people involved
- Result: All three can be charged with conspiracy (third party involved)
Scenario 3 – Exception Does NOT Apply:
- Mr. and Mrs. Bello (Islamic marriage) agree to forge documents
- Just the two of them
- Result: Both can be charged (Section 34 applies only to Christian marriage)
9. Landmark Cases: Understanding Through Real Judgments
Case 1: Balogun v. AG Ogun State (2002) – The “Distinct Evil”
Legal Principle: This case established that the agreement itself is a distinct evil from the substantive crime.[^4]
Significance:
- You can be convicted of conspiracy even if the planned crime never happens
- You can be convicted of both conspiracy and the substantive crime
Example Application:
- Monday: A, B, and C agree to rob a bank (conspiracy committed)
- Tuesday: A, B, and C rob the bank (robbery committed)
- Charges:
- Conspiracy to commit armed robbery (based on Monday’s agreement)
- Armed robbery (based on Tuesday’s action)
Case 2: Njovens v. State – Inference and Two People
Facts: Multiple defendants charged with conspiracy.
Key Holdings:
- Two or more people required: Conspiracy cannot exist with one person[^4]
- Inference from conduct: Conspiracy is “rarely capable of direct proof” and must be “deduced from the acts of the parties directed toward a common purpose”[^4]
Practical Lesson: Prosecutors build conspiracy cases by showing:
- Defendants acted in coordination
- Their actions fit a common plan
- They benefited jointly from the crime
Case 3: Olusola Oyeleye v. The State – Inferring Agreement
Legal Principle: Agreement need not be formal or explicit—it can be inferred from conduct.[^4]
What This Means:
- No need for a written agreement
- No need for recorded conversations
- No need for witnesses who heard them agree
Evidence That Can Establish Agreement:
- Being present together at crime scene
- Coordinated actions
- Division of roles
- Flight together
- Sharing of proceeds
Case 4: Kenneth Clark v. State – Criminal Intent
Legal Principle: The agreement must be entered for the purpose of committing a crime.[^4]
Application: This protects people who unwittingly get caught up in others’ crimes.
Example:
- A taxi driver agrees to drive passengers to a location
- Unknown to him, passengers rob someone at that location
- Result: Driver is not part of conspiracy (no criminal intent)
10. Comparative Analysis: UK, India, and Australia
Understanding how other countries handle conspiracy helps clarify the Nigerian position.
United Kingdom
Unique Feature: England has two types of conspiracy:[^5]
- Statutory Conspiracy (Criminal Law Act 1977): Covers most conspiracies
- Common Law Conspiracy (Preserved for conspiracy to defraud and conspiracy to corrupt public morals)
Why This Matters: The 1977 Act abolished most common law conspiracies, but Nigeria retains the broader common law approach.[^5]
India
Section 120A/B of the Indian Penal Code are identical to Nigeria’s Penal Code Section 96.[^5]
This is because both inherited British colonial law, with Nigeria’s northern region adopting the Indian model.
Significance: Indian case law can be persuasive authority in interpreting Nigeria’s Penal Code provisions.
Australia (Queensland)
Historical Connection: The Nigerian Criminal Code is derived from the Queensland Criminal Code of 1899.[^5]
Key Differences:
| Aspect | Nigeria (Criminal Code) | Queensland |
|---|---|---|
| Terminology | “Felony” (7 years) | “Crime” |
| Misdemeanor Punishment | 2 years imprisonment[^5] | 3 years hard labor[^5] |
11. Practical Scenarios: Analyzing Real Situations
Scenario 1: The Armed Robbery Gang
Facts:
- Emeka, Chidi, and Obiora meet at a beer parlour
- They discuss robbing a filling station
- They agree on roles:
- Emeka will drive
- Chidi will hold the weapon
- Obiora will collect money
- They agree to meet next Friday to execute the plan
- Police arrest them on Wednesday (before the robbery)
Analysis:
Elements of Conspiracy:
- ✅ Agreement: They discussed and agreed on a plan
- ✅ Two or more people: Three people involved
- ✅ Illegal purpose: Armed robbery is a crime
- ✅ Criminal intent: All agreed to commit the crime
- ✅ Inference from circumstances:
- They met and discussed
- They divided roles
- They set a date
Result: All three can be charged with conspiracy to commit armed robbery even though the robbery never happened.
Charges:
- Under Criminal Code: Section 516 (conspiracy to commit felony) → 7 years
- Cannot charge with armed robbery itself (it didn’t happen)
Scenario 2: The Unwitting Accomplice
Facts:
- Ngozi asks her friend Amaka to drive her somewhere
- Amaka agrees and drives
- Ngozi enters a shop and steals items
- Amaka had no idea Ngozi planned to steal
Analysis:
Can Amaka be charged with conspiracy to commit theft?
Elements Check:
- ❌ Criminal intent: Amaka did not intend to commit theft
- ❌ Agreement: Amaka only agreed to drive, not to steal
Result: No conspiracy. Amaka cannot be charged because she lacked the mens rea (criminal intent) required for conspiracy.
Lesson: Merely helping someone who commits a crime doesn’t make you a conspirator unless you knew about and agreed to the criminal plan.
Scenario 3: The Husband and Wife Scenario
Facts:
- Mr. and Mrs. Adeleke (Christian marriage) agree to defraud insurance by faking a burglary
- Just the two of them plan and execute it
- They’re arrested
Analysis Under Section 34:
Can they be charged with conspiracy?
Answer: No (for conspiracy between themselves alone).
Reasoning:
- Section 34 protects husband and wife in Christian marriage from conspiracy charges when conspiring alone
- They are considered “one person” for conspiracy purposes
But: They can be charged with:
- The substantive fraud offence itself
- Obtaining by false pretences
- Any other crimes they actually committed
Limitation: If they involved a third party (even their child), Section 34 protection is lost.
Scenario 4: The Undercover Operation
Facts:
- Sani approaches Officer Musa (undercover) and proposes smuggling drugs
- Officer Musa pretends to agree to gather evidence
- Sani is arrested before any drugs are moved
Analysis:
Traditional Bilateral Approach:
- Two guilty minds required
- Officer Musa had no criminal intent
- Result: Sani might escape conspiracy charge
Unilateral Approach:
- Only Sani’s guilty mind matters
- Sani agreed to commit a crime with someone
- Result: Sani is guilty of conspiracy
Nigerian Position: This is an unsettled area. While Nigeria generally requires two people, there’s “no consensus” on strict bilateral application.[^4]
Likely Outcome in Nigeria: Sani could probably be charged with attempt to smuggle drugs (which doesn’t require two people) even if conspiracy is difficult to prove.
12. Defences and Special Situations
Can You Withdraw from a Conspiracy?
General Rule: Once conspiracy is formed (agreement is made), withdrawal is not a defence to the conspiracy charge itself.
Why? The crime of conspiracy was completed when the agreement was made. What happens afterward doesn’t undo the agreement.
However: Withdrawal may:
- Prevent liability for subsequent substantive crimes
- Reduce sentence
- Show lack of participation in the actual crime
Example:
- Monday: A, B, and C agree to rob a bank (conspiracy complete)
- Tuesday: A says “I’m out, I don’t want to do this” and leaves
- Wednesday: B and C rob the bank
Result:
- A is guilty of conspiracy (it was complete on Monday)
- A is not guilty of armed robbery (he withdrew before it happened)
Conspiracy vs. Attempt
Can you have both?
Yes, they’re distinct:
- Conspiracy: Agreement to commit crime
- Attempt: Taking steps toward committing crime
Example Timeline:
- Day 1: Agreement made → Conspiracy (complete)
- Day 5: Buy weapons → Still just conspiracy (preparation)
- Day 10: Drive to bank with weapons → Attempt begins (execution phase)
- Day 10: Enter bank with weapon → Attempt (clear)
- Day 10: Arrested before taking money → Attempted robbery + Conspiracy
Multiple Conspiracies vs. Single Conspiracy
The Issue: When multiple crimes are planned, is it:
- One conspiracy with multiple objectives?
- Multiple separate conspiracies?
Why This Matters: Different charges, different sentences.
Factors Courts Consider:
- Single agreement or multiple agreements?
- Same parties throughout?
- Crimes related or separate?
- Time frame (continuous or separate periods)?
Example:
- A, B, and C agree to rob three banks over three months
- Likely: One conspiracy with multiple targets
- Alternative: Three separate conspiracies (if agreements made separately)
13. Procedural and Evidentiary Issues
Proving Conspiracy: The Prosecutor’s Challenge
Conspiracy is difficult to prove because:
- Agreements are often secret
- No written contracts exist
- Conversations are private
- Direct witnesses are rare
How Prosecutors Build Cases:
| Type of Evidence | Example |
|---|---|
| Circumstantial | All defendants at crime scene at same time |
| Phone Records | Calls/messages between conspirators |
| Surveillance | Photos/videos of meetings |
| Financial | Money transfers between conspirators |
| Witness Testimony | Co-conspirator turns informant |
| Physical Evidence | Shared weapons, vehicles, documents |
The Hearsay Exception
In conspiracy cases, statements by one conspirator can be evidence against other conspirators (exception to hearsay rule).
Requirements:
- Conspiracy must be independently proven
- Statement made during the conspiracy
- Statement in furtherance of the conspiracy
Example:
- A, B, and C conspire to rob a bank
- A tells X (a witness) “We’re robbing the bank tomorrow”
- Result: This statement can be used against B and C, even though they didn’t say it
Conclusion: The Power and Perils of Conspiracy Law
Conspiracy law gives prosecutors a powerful tool to combat organized crime by intervening before harm occurs. The mere act of agreeing to commit a crime is itself criminal.
Key Takeaways
- Agreement is the crime: You don’t need to complete the planned crime to be guilty
- Two systems in Nigeria: Criminal Code (South) and Penal Code (North) have different approaches
- Five elements must be proven: Agreement, two+ people, illegal purpose, criminal intent, inferable from circumstances
- Rarely directly proven: Courts infer conspiracy from coordinated conduct
- Exception for Christian spouses: Husband and wife cannot conspire alone (but can with third parties)
- Distinct from substantive crime: Can be charged with both conspiracy and the completed crime
- Difficult to defend: Once agreement is shown, withdrawal doesn’t erase the conspiracy
- Powerful prosecutorial tool: Called “the darling of the prosecutor” for good reason[^4]
The Philosophical Foundation
As established in Balogun v. AG Ogun State, the law recognizes that the agreement itself is evil because:
- It converts individual criminal thoughts into group action
- It increases likelihood of execution
- It enhances capability to cause harm
- It makes prevention more urgent
Nigerian law says: When two or more people agree to break the law, the law will intervene—immediately, decisively, and without waiting for them to act on their agreement.
Related Topics
- Legal Reasoning in Judicial Process
- Sources of Law in Nigeria
- Aspects of Law: Understanding Legal Classifications
- Legal Reasoning and Approach to Problems
References
[^4]: The sources for this article are derived from the lecture materials on Conspiracy, with reference to Sections 516-518 of the Nigerian Criminal Code. Case law analysis includes Balogun v. AG Ogun State (2002), Njovens v. State, Olusola Oyeleye v. The State, Kenneth Clark v. State, and Keshiro v. IGP. The common law definition from Mulcahy v. R (1868) as adopted in Majekodunmi v. R is referenced. Section 34 of the Criminal Code regarding husband and wife is analyzed.
[^5]: Sources include the article on conspiracy by Mrabure and Abhulimhen-Iyoha, with reference to Section 96 and Section 97B of the Penal Code, and Section 120A of the Indian Penal Code. Comparative analysis includes the UK Criminal Law Act 1977, the Queensland Criminal Code of 1899, and the American Model Penal Code’s unilateral approach. The overt act requirement under the Penal Code and the distinction between offences and unlawful acts is examined.
This article is part of the LPI 301 Criminal Law series for law students. It is designed as a comprehensive study resource and should not be considered legal advice for specific situations. Always consult a qualified legal practitioner for advice on your particular circumstances.
