As it’s come up a few times in discussions triggered by my post on how Theresa May isn’t a guaranteed shoo-in for the 2017 general election, here are the Crown Prosecution Service’s criteria for deciding whether or not to prosecution election-related offences:

Proceedings for major infringements will normally be in the public interest.

Proceedings for other infringements may not be in the public interest in situations where:

• the offence is of a “technical” nature which does not infringe the spirit of the legislation;
• the offence was committed as a result of a genuine mistake or misunderstanding;
• the offence could not have influenced the result of the election process; or
• the offender has remedied any breach of the law.

If the offence falls to be considered under one or more of the criteria above, the matter may be dealt by way of a caution administered by the police or, where appropriate, the provisions of advice as to an individual’s future conduct.

In practice, it may be difficult to prove that the result of an election has been affected by an infringement. However, the fact that a breach has or may have affected the result of an election is a factor to be taken into consideration in deciding whether proceedings should be instigated. Whilst every case will of course turn on its own facts, where there is clear evidence that a breach has affected the result or is likely to have done so, the public interest is more likely to require a prosecution – even if the infringement itself is relatively minor.

It’s worth in particular noting that a few of the more common reasons that crop up on online chatter either from Conservatives, or reported as being said by Conservatives, do not feature in the criteria.

In particular, the fact that someone might have secured re-election before a court case could proceed against them is not a factor.

Moreover, prosecutions are not restricted to proceeding only on the basis that the offence altered the election result. That’s only required for one very specific set of legal action, which isn’t what’s at stake in the current cases involving so many Conservative MPs.