CH84900 - Penalties for Inaccuracies: Other Penalty Issues: Double jeopardy
You must check the date from which these rules apply for the tax or duty you are dealing with. See CH81011 for full details.
Where a person has been convicted of a criminal offence in respect of an inaccuracy or underassessment, a civil penalty for the same behaviour should not be charged on that person.
Where a person is currently the subject of a criminal investigation, and the time limit for civil penalties on the same behaviour is running out, it may be possible to charge a civil penalty in order to protect HMRC’s position in the event of no conviction. Full guidance may be found in Civil & Criminal Parallel Investigation, and is part of more extensive guidance on parallel civil and criminal investigations.