Type of offence Common law (not defined by statute)
Mode of trial Indictable only (Crown Court)
Maximum Sentence Life imprisonment (in reality, sentences are no where near this and frequently measured in months or single figure years)
Definition The offence is committed where a person:
- does an act (a positive act or series of acts is required; mere inaction is insufficient)
- which has a tendency to pervert and
- which is intended to pervert
- the course of public justice.
What does ‘pervert’ mean?
The word pervert can mean ‘alter’ but the behaviour does not have to go that far – any act that interferes with an investigation or causes it to head in the wrong direction may tend to pervert the course of justice. All the prosecution needs to prove is that there is a possibility that what the suspect has done “without more” might lead to a wrongful consequence, such as the arrest of an innocent person (Murray (1982) 75 Cr. App. R. 58).
What does ‘the course of justice’ mean?
The course of justice includes the police investigation of a possible crime (it is not necessary for legal proceedings to have begun). A false allegation which risks the arrest or wrongful conviction of an innocent person is enough.
What about the ‘intention’?
All that is necessary is proof of knowledge of all the circumstances, and the intentional doing of an act which has a tendency, when objectively viewed, to pervert the course of justice.
False allegations – It is only necessary that the defendant intended that the police should take the false allegation seriously, not that someone is actually arrested.
Double retractions – This is where someone makes a complaint, then retracts the statement claiming the complaint was false, then later, maintains the complaint was true and the retraction was false. It is inappropriate for the Crown to charge two mutually inconsistent charges and invite the jury to decide which is true.
Motoring offences – for an explanation of the procedure in relation to motoring offences whereby the police can demand the name of the driver from the owner of a car see here. An offence will be committed where somebody who knows they are guilty of an offence (say speeding) and is offered a ‘fixed penalty notice’ persuades another to take their points from them (as will be the person who takes them). An example is the case of Henderson  EWCA Crim 1152. Another is, of course, the case of Chris Huhne.
This entirely depends on the facts of the case – fact specific is the phrase often used. This means that the judge will assess the overall criminality, having regard to the following:
- the significance of the substantive offence to which the perverting of the course of justice related;
- the degree of persistence; and
- the effect on the course of justice itself.
CPS Guidance can be found here, including guidance on when it is appropriate to charge in cases involving domestic violence and rape allegations.
Much of the material on this page was taken from the very helpful CPS Guidance.