How Conspiracy Offence Charges Are Decided

A conspiracy offence arises when two or more people agree to commit a criminal act. The law treats conspiracy as a distinct inchoate offence - one that can be pursued even if the substantive crime has not been completed - because the mere agreement to commit wrongdoing poses a risk to public safety and undermines the rule of law. In England and Wales, conspiracy offences are governed primarily by statutory law, and decisions about charging are carefully assessed by investigators and prosecutors before any formal charges are issued. This article explains the legal framework for conspiracy, how conspiracy charges are decided, who makes those decisions, procedural issues, the role of evidence, and what defendants and the public should understand about the process.

Legal Basis of Conspiracy Offences

Statutory Definition

The principal statutory offence of conspiracy in England and Wales is set out in section 1(1) of the Criminal Law Act 1977. Under this provision:

• A person is guilty of conspiracy if they agree with at least one other person that a course of conduct shall be pursued which, if acted upon, will involve the commission of an offence.

This agreement itself creates criminal liability, even if no further steps are taken or the planned act never occurs.

Scope and Substantive Offences

A conspiracy charge must relate to a specific underlying offence or set of offences that would be criminal if committed in England and Wales. The substantive offence contemplated by the agreement determines both the nature of the conspiracy charge and the potential penalties.

There are exceptions to conspiracy liability under the Act, such as where the only other person to the agreement is a spouse or intended victim of the planned offence.

How Investigators and Prosecutors Decide to Charge Conspiracy

Police and Investigators Gather Evidence

Conspiracy investigations may begin as part of wider criminal enquiries, such as serious fraud, drug trafficking, terrorism, or organised crime. The police, National Crime Agency (NCA) or specialist agencies such as the Serious Fraud Office (SFO) gather evidence suggesting that individuals have reached an agreement to commit wrongdoing.

Unlike substantive offences where actions might be overt, conspiracy focuses on establishing the agreement and shared intent. Investigators look for evidence such as communications between the parties, planning documents, financial transactions, and admissions that imply an understanding to pursue criminal conduct.

The Role of Prosecutors

Once investigators believe there is a realistic case for conspiracy charges, the file goes to the Crown Prosecution Service (CPS). Prosecutors apply the Code for Crown Prosecutors to decide whether to authorise charges. This involves two tests:

1. Evidential Test – Is there sufficient admissible evidence to provide a realistic prospect of conviction for conspiracy?
2. Public Interest Test – Is it in the public interest to prosecute?

Only when both tests are satisfied will the CPS authorise a formal charge. Prosecutors are required to select charges that reflect the seriousness and extent of the offending supported by evidence.

Consent Requirements

In some specific scenarios, additional consent from senior officials may be required before prosecution can proceed. For example:

• Conspiracy to commit purely summary offences (less serious offences heard only in magistrates' courts) normally requires consent of the Director of Public Prosecutions.
• If the conspiracy involves conduct that would occur outside England and Wales, Attorney General's consent may be necessary.

These consent requirements ensure that prosecutorial decisions in borderline or complex areas are subject to appropriate oversight.

Elements Prosecutors Must Prove

To secure a conviction for conspiracy, prosecutors must establish three core elements:

1. Agreement - Two or more people must have agreed to pursue a course of conduct that involves committing a crime.
2. Intention - The parties must have intended that the agreement be carried out and realised that the conduct would constitute the substantive offence.
3. Knowledge - The defendant must know or appreciate the essential circumstances of the intended crime.

Importantly, an overt act in furtherance of the plan is not required for statutory conspiracy: the offence is complete once the agreement is made.

Charging Decisions in Practice

Conspiracy Alongside Substantive Crime

In many cases, conspiracy charges are issued alongside charges for the substantive offence. For example, if evidence suggests that a group agreed to commit fraud and then carried out elements of the fraud, prosecutors may charge both conspiracy to defraud and substantive fraud offences. This dual approach recognises both the planned wrongdoing and the actions taken.

Conspiracy Without Substance

Conspiracy can also be charged even if the underlying crime was never committed. Because the offence centres on the agreement and shared intent, prosecutors may pursue conspiracy where parties planned criminal conduct but never executed it. This reflects the principle that organised wrongdoing is harmful even at the planning stage.

Selecting Appropriate Charges

CPS guidance emphasises that prosecutors should not pursue more charges than necessary merely to secure a plea deal or conviction. Decisions should be proportionate, clear, and tailored to the evidence of involvement and culpability.

Where Conspiracy Cases Are Heard and Penalties

Court Jurisdiction

Conspiracy is typically a serious indictable offence, meaning it is tried before a Crown Court. This reflects the significance of conspiracy to public safety and complex nature of evidence.

Sentencing

Sentences for conspiracy vary according to the gravity of the planned offence:

• If the conspiracy relates to a serious crime such as murder or an offence punishable with life imprisonment, sentences can reflect the maximum penalty for that substantive offence.
• For less severe offences, sentencing remains linked to the seriousness of the underlying intended crime.

There is no fixed statutory maximum for conspiracy in general; instead, sentencing aligns with the relevant substantive offence to ensure proportionality.

Practical Considerations

Evidence Challenges

Prosecutors often face challenges in conspiracy cases because the agreement is rarely documented in writing. They must rely on circumstantial evidence, such as patterns of communication, behaviour consistent with planning, or coordinated steps taken in furtherance of the plan.

This reliance on inference places importance on high‑quality investigations and forensic analysis to support charging decisions.

Defences and Legal Nuance

Defendants may argue that no genuine agreement existed or that they lacked requisite intent or knowledge. Given the complexity of proving a conspiratorial agreement, legal defence strategies often focus on challenging the evidence of collusion or shared purpose.

Common Questions from our Readers

Can someone be charged with conspiracy if the crime never happened?
Yes. The essence of conspiracy is the agreement to commit a crime, so a charge can be laid even if the planned offence was never carried out.

Who decides whether to charge a conspiracy offence?
Investigators gather evidence, but the formal decision to charge is taken by prosecutors in the CPS, applying strict evidential and public interest tests.

Does conspiracy require action beyond agreeing?
No. Under English law, conspiracy is complete on agreement alone; no further action need be taken.

Summary

In England and Wales, conspiracy offences are governed by the Criminal Law Act 1977 and arise from an agreement between two or more people to commit a criminal act. Charging decisions are driven by evidence gathered by police and specialist agencies, reviewed by the Crown Prosecution Service against strict tests of sufficiency and public interest. A conspiracy charge may be pursued alongside substantive offences, or alone where an agreement exists. Penalties reflect the seriousness of the intended crime, and cases are typically heard in the Crown Court. Understanding how conspiracy charges are decided helps defendants, solicitors and the public appreciate the structure and seriousness of these prosecutions.