‘In his email Mr Smith advises that in January 2013 the rules of child benefit changed … Mr Smith’s child benefit was applied for 10 years ago, before this rule applied. … Mr Smith has no problem paying the tax owed but believes it is unfair to then add a 20% penalty because “HMRC took 4 years to contact”. Mr Smith would like to know why it has taken 4 years to be informed of this tax bill and why he is also being penalised for what he believes is an oversight by HMRC.’