Checkout system looks up unique ID and finds it has been sold previously

WARNING - CODE RED

Checkout operator:

• Item ID: 0bc2c6fc9e76e04c5900963332f90334
• Previously sold on 13Sep12-1035.34hrs
• Notices that screen has gone red denoting an irregularity - item has already passed through a checkout.
  (Note: A similar incident would occur if the item was beyond its shelf-life/use-by date.)
• Advises customer in a non-alarmist manner: "Sorry Sir/Madam, this article seems to be faulty. I will have it replaced."
• Store management automatically alerted in the case of a serious incident such as the item already having been through a checkout on a previous occasion.

Fig 1. Items being monitored during transporation

New item fetched and given to customer

Suspect item put to one side for further examination by shop management or police per standing operating procedures.