Criminal Law Act 1977: Conspiracy and Related Offences

Introduction

The Criminal Law Act 1977 reshaped the law of conspiracy in England and Wales. It put a statutory definition of conspiracy on a clear footing, limited who can be a party to the offence, and abolished most common law conspiracies (with a notable exception). In practice, it sits alongside the Criminal Attempts Act 1981 (attempts) and the Serious Crime Act 2007 (assisting or encouraging), which together cover planning, trying, and helping crimes.

This guide sets out the essentials in a scannable format, clarifies contested points such as the mental element for conspiracy and attempt, and links the Act to leading cases you are likely to see in study and practice.

What You'll Learn

• The statutory definition of conspiracy under section 1 Criminal Law Act 1977
• How agreement, intention, and knowledge work for conspirators
• Who is excluded by section 2 (spouses/civil partners, children under 10, intended victims)
• How attempts are defined under the Criminal Attempts Act 1981, including “more than merely preparatory”
• When impossible attempts still attract liability
• How the Serious Crime Act 2007 covers assisting or encouraging offences
• Jurisdictional extensions for conspiracies and attempts tied to conduct abroad
• The key cases: Anderson, Yip Chiu Cheung, Saik, Gullefer, Geddes, Campbell, AG’s Ref (No 3 of 1992), Pace and Rogers, and Sadique (No 2)

Core Concepts

Statutory conspiracy: agreement, intent, and scope

• Definition: Section 1 Criminal Law Act 1977 creates the offence where two or more persons agree to pursue a course of conduct which, if carried out in accordance with their intentions, will amount to or involve the commission of an offence.
• Agreement: There must be a genuine meeting of minds. It can be express (words) or inferred from conduct. It is not enough for people separately to have the same idea; the prosecution must show a shared plan.
• No need for an overt act: Unlike some common law approaches, the statutory offence is complete once the agreement is made. No step towards the offence need be taken, though practical evidence often comes from acts that show the agreement exists.
• Mens rea: The defendant must intend to agree and intend that the course of conduct will involve the commission of the offence. The debate from R v Anderson [1986] AC 27 suggested intention to carry out the plan might not be required, but later authorities (notably Yip Chiu Cheung v R [1994] and R v Saik [2006] UKHL 18) emphasise the need for intention that the offence be committed, at least by someone, and appropriate knowledge of any elements that require it.
• Retained common law: Most common law conspiracies were abolished, but conspiracy to defraud remains.

Exemptions and limits under section 2

Section 2 excludes liability where the only other party to the agreement is:

• The defendant’s spouse or civil partner
• A child under the age of criminal responsibility (under 10)
• The intended victim of the offence

Practical points:

• If there is at least one other conspirator outside these categories, the exemption does not apply.
• An “intended victim” includes, for example, the target of a fraud. The law avoids labelling mutual arrangements with a sole intended victim as conspiracy.
• The offence requires at least two parties capable in law of conspiracy. A defendant cannot conspire alone.

Attempts under the Criminal Attempts Act 1981

• Definition (s1): A person is guilty of attempt if, with intent to commit an offence, they do an act which is more than merely preparatory to the commission of the offence.
• “More than merely preparatory”: The courts ask whether the defendant has moved from preparation to a step that is part of executing the offence. Gullefer [1990], Geddes [1996], and Campbell [1991] show the line can be tight: lying in wait or reconnoitring is often still preparatory; entering the zone of execution and beginning the offence points toward attempt.
• Impossibility (s1(2)): A person can be guilty of attempting the impossible (e.g., trying to handle stolen goods that are not in fact stolen), provided they intend the offence judged on the facts as they believe them to be.
• Mens rea: For conduct and consequence elements, intention is required. For circumstance elements, the approach varies by offence type. Khan [1990] allowed recklessness as to the victim’s consent for attempted rape; AG’s Ref (No 3 of 1992) accepted intention for the missing element plus recklessness for the other element. Pace and Rogers [2014] took a stricter view for property crimes: where the full offence requires knowledge, suspicion or recklessness is not enough for attempt.

Assisting or encouraging offences (Serious Crime Act 2007)

The SCA 2007 introduced offences of:

• Intentionally encouraging or assisting (s44)
• Encouraging or assisting believing the offence will be committed (s45)
• Encouraging or assisting believing one or more of a number of offences will be committed (s46)

Key difference from conspiracy: no agreement is needed. R v Sadique (No 2) [2013] EWCA Crim 1150 confirms that under s46, it is enough to believe that one of several offences will be committed; the law does not require certainty about which one.

Jurisdiction and offences with a foreign element

• Conspiracy abroad: Section 1A Criminal Law Act 1977 (inserted by the Criminal Justice (Terrorism and Conspiracy) Act 1998) covers agreements in England and Wales to commit offences abroad in specified circumstances.
• Attempts abroad: Section 1A of the Criminal Attempts Act 1981 (inserted by the Criminal Justice Act 1993) allows prosecution for attempts connected to offences triable in England and Wales, even if the substantive offence would occur outside the jurisdiction.
• These provisions help address cross‑border criminal planning and preparatory acts.

Key Examples or Case Studies

• R v Anderson [1986] AC 27

  • Issue: Is intention that the offence be committed required?
  • Takeaway: Suggested it is enough that the defendant intended to play some part in the plan, even if they did not intend the offence to be carried out. Later cases limit this reading.

• Yip Chiu Cheung v R [1994]

  • Issue: Undercover agent as co‑conspirator.
  • Takeaway: Each conspirator must intend that the offence be committed. An undercover agent who does not intend the offence cannot be a true conspirator; the genuine conspirator is still liable.

• R v Saik [2006] UKHL 18

  • Issue: Knowledge for conspiracy to launder money.
  • Takeaway: Where the substantive offence requires knowledge (e.g., property is criminal), the conspirator must at least know or believe that element; suspicion is not enough.

• R v Gullefer [1990] 1 WLR 1063

  • Issue: What is “more than merely preparatory” for attempt?
  • Takeaway: Acts still preparatory (e.g., trying to trigger a refund scheme before the offence starts) are not attempts.

• R v Geddes [1996] Crim LR 894 and R v Campbell [1991] 93 Cr App R 350

  • Issue: Lying in wait or possessing items near the scene.
  • Takeaway: Being poised to commit a crime may still be preparatory unless the defendant has begun the offence itself.

• Attorney General’s Reference (No 3 of 1992) [1994] 1 WLR 409

  • Issue: Mens rea where one element of the full offence is “missing”.
  • Takeaway: Intention as to the missing element with recklessness as to the other can suffice for attempt in some offences involving combined elements.

• Pace and Rogers [2014] EWCA Crim 186

  • Issue: Attempted handling of stolen goods when goods were not stolen.
  • Takeaway: For attempt to commit offences requiring knowledge, mere suspicion or recklessness does not meet the mental element; intention to commit the full offence is needed.

• R v Sadique (No 2) [2013] EWCA Crim 1150

  • Issue: Assisting or encouraging “one or more of a number of offences” under SCA 2007 s46.
  • Takeaway: The defendant need not predict the exact offence; belief that at least one offence in a class will be committed can be enough.

Practical Applications

• Choosing the right charge

  • Use conspiracy where there is evidence of an agreement between at least two legally capable parties.
  • Use SCA 2007 where there is assistance or encouragement but no agreement.
  • Use attempt where the defendant has crossed from preparation to execution with intent to commit the crime.

• Proving agreement

  • Rely on messages, meetings, and coordinated conduct to show a shared plan.
  • Remember: an undercover officer who does not intend the offence is not a true conspirator. If the only “other” party is an undercover officer, conspiracy cannot be made out (but SCA 2007 might apply).

• Applying section 2 exemptions

  • Check whether the only other party is a spouse/civil partner, a child under 10, or the intended victim. If so, conspiracy is not made out unless there is at least one other adult conspirator.

• Mens rea pitfalls

  • For conspiracy, be prepared to explain Anderson, then show how Yip Chiu Cheung and Saik point to intention that the offence be committed and appropriate knowledge for elements that require it.
  • For attempt, identify each element of the full offence and state clearly which elements require intention and whether any circumstance element may accept recklessness (limited and offence‑specific).

• Establishing “more than merely preparatory”

  • Map the steps of the planned offence. Acts within the “execution” phase (e.g., pointing a loaded gun at a victim, getting into the victim’s car to attack) are strong evidence of attempt; mere preparation (buying tools, travelling, reconnaissance) may not suffice.

• Handling impossibility

  • Attempts: impossibility due to facts unknown to the defendant is no defence.
  • Conspiracy: focus on whether the shared plan, if carried out as intended, would involve an offence; operational impossibility will not usually help the defence.

• Cross‑border planning

  • Consider s1A CLA 1977 and s1A CAA 1981 where the plan or attempted conduct has an overseas element but there is a strong link to England and Wales.

• Sentencing and exposure

  • Sentences for conspiracy often track the seriousness and statutory maximum of the agreed offence.
  • Assisting/encouraging and attempts can still attract substantial sentences even if the full offence was not completed.

Summary Checklist

• Know the statutory definition of conspiracy under CLA 1977 s1
• Prove agreement plus intention that the offence will be committed (apply Anderson, Yip Chiu Cheung, Saik)
• Apply section 2 exemptions: spouse/civil partner, under‑10s, intended victim
• Remember: no overt act is required for conspiracy; the agreement is the actus reus
• For attempt (CAA 1981), show intent to commit the offence and acts more than merely preparatory
• Treat impossibility as no defence to attempt; for conspiracy focus on the plan as intended
• Use SCA 2007 where there is assistance or encouragement without agreement; s46 covers belief that one of several offences will occur
• Consider jurisdiction: s1A CLA 1977 (conspiracy abroad) and s1A CAA 1981 (attempts with a foreign element)

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