Hampshire Police is the first force to evaluate the vehicle, which will be fitted out to full police specification.
John Bradley, Hampshire Police’s fleet manager, said: ‘We have already received positive feedback from our officers after an initial trial and know that the vehicle’s performance was outstanding, with quick acceleration and more than adequate response throughout the range of the electronic gearbox.
‘We eagerly await the fully equipped model when we will be able to put it through its paces and gauge the performance under police operational conditions.’
Bradley said all fleet managers needed to consider a vehicle’s environmental impact when buying new models. His fleet covers 14.5 million miles per year and uses 390,000 litres of fuel.
The RX400h features a hybrid power system designed to reduce emissions and increase efficiency without compromising on performance. It sports a 3.3-litre V6 engine with a 165bhp front electric motor, high voltage battery and generator. A second rear electric motor automatically engages the vehicle electric four-wheel drive, known as E-Four, when required.
A computer in the car automatically works out the most efficient balance between the motors.