The Upper Tier Tax decision in Perrin provides a detailed explanation of the concept of a reasonable excuse.
At 20 pages it is not the longest decision; and is worth a read if you or a client wishes to appeal an HMRC decision on reasonable excuse grounds.
Towards the end of the decision there are three important details:
- What are the facts? What evidence exists for those facts (para 81)?
- Ignorance of the law is usually no excuse (para 82).
- HMRC’s oft-quoted phrase that a reasonable excuse has to be based on ‘unforeseeable or inescapable’ circumstances is highlighted as a faulty argument.
Here is the full decision: http://www.bailii.org/uk/cases/UKUT/TCC/2018/156.html
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