Methods of unattended detection of operator's deliberate or unintentional breaches of the operating procedure and devices therefore

Method and device is proposed herein for unattended detection of deliberate or unintentional breaches caused by an operator of a routinely executed procedure comprising transference of objects and their mandatory presenting to the item-sensing device for registration or testing or classification. The invention can be used for detecting fraud of a cashier in checkout retail environments by omitting registration of items placed on the take-away belt. The invention is based on detecting motion and presence events in the predetermined workspace areas and comparing their temporal sequence with the predetermined scenarios. In the case of coincidence with the scenario, the sensing device signal in the due time is checked to be received. In the case of a wrong or no signal received, the procedure is recognized as incorrectly executed. Motion and presence events are detected by computer analysis of live video from the camera and/or by applying the motion and the presence detectors.