A teenager gunned a man down outside a petrol station over a comment that he "looked like the Milky Bar Kid", and he is still on the run from police, a trial heard.
John Pordage, 34, was killed by a single shot to the chest at a BP garage in Chelmsford, Essex.
Tracy Ayling QC, opening the prosecution case, said that either Mr Pordage or a friend told alleged gunman Bradley Blundell that he looked like the Milky Bar Kid.
The prosecution allege that Blundell, who was 17 years old at the time and is now on the run from police, shot Mr Pordage dead.
Chelmsford Crown Court heard Blundell was one of three male passengers in the back of a car while its female driver filled it with fuel.
Ms Ayling said Mr Pordage or his friend made "flirtatious remarks" to the driver, including that she had a "nice bum".
"Further comments were made, this time towards the males in the back of the (car), particularly in reference to Bradley Blundell," Ms Ayling said.
"Reference was made to him looking like the Milky Bar Kid.
"It may well be that that remark was the catalyst for what followed."
The male passengers then got out of the car and there was a confrontation which ended in Mr Pordage being shot, Chelmsford Crown Court heard.
"The reason for the shooting appears to be no more than either Mr Pordage or the friend he was with remarked that the driver of the car Mr Blundell was in had a nice bum," said Ms Ayling.
She continued: "The man who allegedly did the shooting, Bradley Blundell, now 18 years old, disappeared on the night of the shooting and has not been found to be arrested and to stand his trial."
Two other teenagers are on trial at Chelmsford Crown Court.
A 16-year-old boy, who cannot be named for legal reasons, denies Mr Pordage's murder.
It is alleged that he got out of the car armed with an extendable baton - and while he did not fire the gun, he was acting together with Blundell and intended that Mr Pordage "suffer at least really serious bodily harm".
Saul Stanley, 18, of no fixed address, denies two counts of possessing a prohibited firearm - a sawn-off shotgun and a converted revolver - two counts of possessing ammunition without a firearms certificate and one count of possessing prohibited ammunition.
Ms Ayling said: "There's no doubt that Saul Stanley held back and that's why he's not charged with murder."
Both Stanley and the 16-year-old boy deny attempting to pervert the course of justice by, together with Blundell, destroying or disposing of evidence including weapons, clothing and telephones.
Mr Pordage was returning from a nightclub and on his way to buy cigarettes when he was attacked at around 2.10am on August 5 last year at the garage in Baddow Road.
The group in the car were returning from Brentwood where they had gone to collect a stolen motorcycle, Ms Ayling said.
She said Mr Pordage's friend told police that one of the teenagers "was arguing, trying to be a big man when he held the bag up and shot him twice".
He said the weapon "looked like a homemade gun, but it was in a blue carrier bag", Ms Ayling added.
The trial continues.