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WITNESS simulation software from the Lanner group is used to improve Control Room operations, monitor the efficiency of vehicle response to incidents and optimise the use of custody suites county-wide


The Control Room, where 999 calls are received, is usually the first point of contact with the public needing police services, and effective working practices are essential to provide the best service possible. High speed response is paramount. The performance indicators that Norfolk Police sets itself are unequivocal: 88% of incoming calls should be answered in less than ten seconds, response to emergency calls in urban areas should take less than 10 minutes and for rural areas, less than 15 minutes.

The accuracy of the modelling was quick to prove itself. For example the model came up with the figure of 25 calls on average missing the response-time target each day; the actual, ‘real-life’ number was between 25 and 26.

The model subsequently showed that the idea of identifying dedicated 999 call-takers would solve much of the problem, and a decision was taken to implement the system. As well as verifying the effectiveness of the new operating procedures, the model was used to prove the case for more staff, new equipment and a new shift pattern – recommendations that have now all been adopted.

Vehicle Response Times

Norfolk Police then built a WITNESS model in a drive to enhance vehicle response times.

“Again it was a question of measurement,” Inspector Brighten explains. “We had no data on how much time police vehicles were spending travelling to incidents. Ours is a large geographical area, with a seasonally-variable population, and we had no system to measure the effectiveness of changes to the location and availability of units. We needed a better understanding of the logistics of incident response, and the effect of deploying extra staff in busy periods".

Information fed into the model included details of actual incidents, their location, the time it took to send out a police unit, the location of the nearest unit, the time it spent travelling to the scene and the time spent at the scene. This model enables Norfolk Police to measure almost all elements of vehicle response, and allocate resources accordingly. It has identified times for each stage of the incident call, taking into account variables such as traffic density, type of incident and possible travel speed.

Custody Suites

As well as operating in the front lines, WITNESS is helping Norfolk Police in the back room. A simulation model is being used to access changes in the way custody suites are being used.

Inspector Brighten explains: 

“As well as a ‘duty of care’ to our prisoners we are rationalising the use of custody suites across the County, and investigating the possibility of cross-force boundary co-operation. Along with the specialised resources and substantial outlay involved in compulsory cell modifications and the installation of, for example, CCTV systems, all this adds up to change which needs careful evaluation and management.”

“Since WITNESS had proved so useful in the change management involved in the implementation of the new Control Room, and the evaluation of the Vehicle Response System, we are using it again to assess the impact of changes to enable us to arrive at the best possible use of custody suites.”

The model will examine elements such as cell capacity requirements, the number and sex of custody staff and shift patterns, different types and sex of prisoners, and their custodial requirements.

“WITNESS does not in itself present solutions,” Inspector Brighten states, “But it gives us an invaluable tool to test the effectiveness of the solutions that we propose, and to examine, evaluate and verify a whole range of ‘what if?’ options. The beauty of WITNESS is that it enables painless experimentation.”


The improvements since the WITNESS-verified Control Room procedures have been put in place are impressive. Now almost 95% of 999 calls are picked up inside the 10 second target.

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