Conspiracy as the name implies involves criminal activity by two or more individuals.

That criminal activity is not what the individuals actually did but what they planned to do and the planning must be in relation to doing something which would be a crime if it was actually carried out.

It follows that if the planning were actually carried out a substantive offence would be committed, and in such circumstances the Prosecution would normally charge the substantive offence.

There are, however, a number of reasons why although the substantive offence has taken place the Prosecution will still charge the offence of conspiracy:

  1. Where there is insufficient evidence to charge the substantive offence.  For example, where a number of people are suspected of supplying drugs the Prosecution may be able to prove that the drugs were supplied to an individual or individuals without difficulty but there may be a number of people (not necessarily known to each other) in the supply chain whose intercepted communications make it quite clear that they are involved in the chain – producer, financier, courier or dealer – but it may not be possible to connect them individually to a particular street deal.  They will all be involved in a conspiracy to a larger scheme to which they were “attaching themselves.”Another example might be a Conspiracy to Defraud. (Still a Common Law Offence) This is another example where a number of people might be involved in setting up arrangements so as to carry out a fraud on an individual or individuals but they may not all individually know the details of the fraud itself. They will nevertheless be guilty as conspirators if they were in fact instrumental in the fraud taking place “party to the common desire” and they were at least aware that there was a larger scheme to which they were attaching themselves. It is perhaps ironic that in these cases, although the substantive offence is not charged that the evidence often adduced by the Prosecution to prove the conspiracy is not so much the covert communications between the conspirators but the evidence of what they actually did from which the planning stages of the substantive offence – i.e. the conspiracy – can be inferred.
  2. Where the Prosecution consider that the scale of the offending is so great that sentencing for each individual substantive offence would not be sufficient and they want the Court to consider the offending as a whole – i.e. over a period.  Drugs supply is a good example of this.
  3. Where the Prosecution want to use communications between the various conspirators to incriminate not just the person who made the communication but the person to whom it is addressed.  In the offence of conspiracy the actions and admissions of one party (not a confession on arrest or during an interview under caution) may be used in evidence against another party.  This is a notable exception to the general rule where the Defendant is not to be prejudiced by the actions or statements of a Co-defendant.

If a substantive offence has not been committed the Prosecution may have a choice between conspiracy and another “inchoate” offence (i.e. where the crime never took place) such as Attempt or Incitement.  Conspiracy to pervert the course of justice is a good example.  Suppose two people agree for a motorist to sign a Road Traffic Act Declaration to say he was the driver of a car which exceeded the speed limit in order to save the actual driver (the second conspirator) from having penalty points endorsed on his licence, the offence of conspiracy is committed even before the motorist making the declaration is summonsed or convicted of the speeding offence. If there is a summons or automatic points then the course of justice has been perverted and substantive offence of Perverting The Course of Justice will be charged. (This was the case for the hapless Chris Hume who was, you may remember, convicted of the substantive offence of perverting the course of justice because in his case the offence was discovered long after points were endorsed on the licence of his equally hapless Co-defendant wife, Vicky Pryce.)

Conspiracy is an Indictable Only offence, which means it can only be tried in the Crown Court, so according to present practice a Defendant charged with the offence will originally appear in the Magistrates’ Court which will – normally at the first Hearing – transfer it to the Crown Court.

The maximum sentence for conspiracy on conviction is life imprisonment.


Nb. This guide is intended to give general information only and not intended to be used as the basis upon which Advice is given nor should it be relied upon as giving advice specific to a case or individual and Lawtons do not accept liability for anyone using this guide. Should you require specific advice in connection with a real case or situation, please contact us immediately so that we can provide specific Advice