No one could be seen in the driver's seat and Patel appeared to have his hands behind his head. The witness, who was a passenger in another car, filmed Patel as the car drove past.
Witness accounts stated that traffic was heavy due to congestion and it has been estimated that the vehicle was travelling at approximately 65km/h at the time.
Footage of the incident was first posted on social media before it was reported to police and a Notice of Intended Prosecution was then sent to Patel in the post.
He was later interviewed by officers at Stevenage Police Station, where he admitted that he knew what he had done was 'silly', but that the car was capable of something 'amazing' and that he was just the 'unlucky one who got caught'.
As part of the investigation, officers obtained a statement from a Tesla engineer who described autopilot as a 'suite of driver assistance features'.
They stated that these are hands-on features intended to provide assistance to a 'fully-attentive driver'.
Traffic-Aware Cruise Control (TACC) assists with acceleration and deceleration of the vehicle whilst Autosteer provides assistance with steering of the vehicle.
Further literature provided by Tesla states that drivers should 'never depend on TACC to adequately slow down model S, always watch the road in front of you and be prepared to take corrective action at all times. Failure to do so can result in serious injury or death'.
Investigating officer PC Kirk Caldicutt, from the Bedfordshire, Cambridgeshire and Hertfordshire Road Policing Unit, said: "What Patel did was grossly irresponsible and could have easily ended in tragedy. He not only endangered his own life but the lives of other innocent people using the motorway on that day.
"This case should serve as an example to all drivers who have access to autopilot controls and have thought about attempting something similar. I want to stress that they are in no way a substitute for a competent motorist in the driving seat who can react appropriately to the road ahead."
