CH402704 | Charging Penalties: establishing penalty behaviour: evaluating evidence: evidence of a careless inaccuracy
From HM Revenue & Customs · Compliance Handbook
You may identify a number of elements which individually or collectively may indicate that the inaccuracy was due to the person not taking reasonable care, such as:
not enough time given to maintaining the necessary records
no check of the figures
advice not sought where necessary
uncritical acceptance of advice
not giving an adviser or HMRC the full facts when seeking advice
not checking the work done by an adviser
not acting on the advice given
not using the records or systems at their disposal
relying on unreasonable estimates
relying on uncorroborated statements from third parties
Further guidance on and examples of careless inaccuracies are in the technical guidance CH81100.
In order to conclude, on the balance of probabilities, that there was a failure to take reasonable care, you must be able to present evidence and a reasoned argument to show:
the steps that, if taken, would be considered reasonable care
that there was a failure to take those steps
why it was reasonable to expect the person to take those steps, taking into account their abilities and circumstances