Dashcam footage has been released showing police vehicles following Chris Kaba before he was shot dead by a Met marksman.
Martyn Blake, 40, is on trial at the Old Bailey accused of murder after he shot the 24-year-old through the window of an Audi.
The officer claims that he feared for the safety of colleagues who could have been run over as Mr Kaba tried to escape.
The jury were shown a video of officers following Mr Kaba through South London on September 5, 2022, after the registration plate of the Audi was flagged as being the same vehicle involved in a shotgun incident the night before.
At one point Mr Kaba attempted to flee by ramming a police car leaving Blake was “horrified” believing “one or many” colleagues could be killed or “crushed” by the driver using the car “as a weapon”, the defence claim.
But Prosecutor Tom Little, KC, accused the firearms officer of presenting a “false and exaggerated” account to justify his shooting.
Mr Kaba realised that he was being tailed by officers just seconds before a police car blocked him in on a residential Streatham street at 9.55pm.
He tried to get away by revving forward and then reversing into a police car, but ended up wedged between parked cars, the court heard.
Ten officers swarmed around the Audi shouting “armed police, show me your hands” seconds before Blake shot him in the head.
Blake, who has pleaded not guilty to murder, said he opened fire because he feared there was an “imminent threat” from the driver who was found later to be unarmed, the court was told.
He said: “I had a genuine belief that either of us could be killed.
“The driver then rammed our car, which was behind me, as well as a parked car and stopped, wedged.
“Seeing the car was stopped I went round to the front and again challenged the driver saying something like 'armed police, stop the vehicle’.
“At this point the driver reversed back at great speed as fast as he could, directly towards my colleagues who were out on foot approaching the vehicle.
“The male had already shown a propensity to use violence and was happy to use any means to escape.
“I had a genuine held belief that one or many of my colleagues could be killed by the car, and that the driver would not stop his attempt to escape at any cost.
“I then made the decision to incapacitate the driver due to the imminent threat to my colleagues and took one shot at the driver.
“He immediately slumped and the car stopped.”
But Mr Little told the Old Bailey that the car was stationery at the time of the shooting and the victim posed no lethal threat, saying: “That account is false, we say, in parts, and exaggerated in other parts.”
Mr Little said: “At the point at which the defendant discharged his firearm the Audi was stationary. Chris Kaba’s hands were on the wheel and were visible to the defendant.
“There was no revving as described, there was no potential firearm in his hand, and it was far from certain that if he tried again (to drive through the gap) he would he through instantaneously.
“There was no firearm in that vehicle and the defendant does not suggest that there was any movement by him of his hands to make him think that he was reaching for a firearm.”
Meanwhile Patrick Gibbs, KC, defending, said Mr Kaba had been using his car as a “battering ram” and jurors should consider “what did Martyn Blake honestly believe in the moment about the risk to his colleagues over and above himself.”
