The 'ERA' system
Prior to self-assessment, the Inland Revenue would screen Returns received, marking them with an 'E', 'R' or 'A', as follows:
Investigation cases, where a fundamental review is envisaged, or where there has been a failure to meet relevant obligations at the correct time.
Cases marked ‘R’ are those where the Revenue consider that a review by a more senior officer is required but do not expect to perform a full investigation including the examination of underlying records. This might encompass looking at computational errors, or dealing with complex technical issues.
If the Revenue accept the information provided, they mark it ‘A’ where no further action is required, or ‘A+’, if some action is required by an Inspector, such as responding to points raised by an accountant.
Note that the screening took place at the point of entry of the data. Contrast this with the ‘process now, check later’ philosophy of self-assessment, which enables greater resource to be utilised in countering avoidance.