MHRA proposes ‘due diligence’ defence for dispensing errors

Is there anything as a 'simple dispensing error' and how can you prove due diligence if you have made a mistake which must show that you did not show due diligence or else the mistake would not have happened !
Why cannot the MHRA just help to decrimalise dispensing error's ,i do not go to work like all pharmacist wanting to make a error but i am human so errors will happen.

Section 64 I believe was a carry over from the 1955 Food Act and was about preventing deliberate adulteration of products for personal gain and thus strict liability was involved as either the product was or was not supplied to specification by the healthcare practitioner involved. It should thus not be about a pharmacist or other supplier of dispensed medicines seeking to prove innocence against this section, but for the CPS using existing laws under a presumption of innocence to demonstrate beyond reasonable doubt that criminal negligence took place in that supply process . If it is not going to be used for the purpose intended it should be withdrawn from the Act.