A carer is facing life in jail after he was found guilty of carrying out a gunpoint execution "as bizarre as it is brutal" outside a trendy nightclub.
Andrew Denty, 30, shot Curtis Smith with a Mac-10 machine gun as they left Club Red in east London while revellers, including a Radio One DJ, partied inside.
The Old Bailey heard that the DJ, who was not named, gave a statement to police but was "fearful" about people knowing what he said.
Denty blasted 36-year-old Mr Smith in the back of the head after developing a "festering hostility" towards him, the court was told.
Both men worked as carers for Denty's brother Clifford, who was paralysed from the neck down after being shot himself in the past.
But the defendant had grown resentful of his brother's growing dependence on Mr Smith who would sometimes stay over at the family home to help give 24-hour care.
Curtis Smith was shot after helping Clifford into an adapted Mercedes car-van following a night out at the club in the Limehouse area in July last year.
Aftab Jafferjee QC, prosecuting, told jurors: "This case is as bizarre as it is brutal - bizarre in that one carer of a victim of gun crime is gunned down by the other carer.
"It is brutal in that Curtis Smith is effectively executed, shot in the back of his head by a Mac-10 machine gun."
There were cries of "yes" from the victim's family as Denty, shaking his head, was found guilty of murder.
The defendant, of Fraser Street, Waterloo, south east London, faces a life term with a minimum of around 30 years in jail and was remanded in custody to be sentenced on 17 July.
George Ogaba, 19, of Leontine Close, Peckham, was cleared of a charge of perverting the course of justice relating to allegations that he helped hide the murder weapon.
Denty's cousin Emmanuel Okot, 25, of Athena Court, Waterloo, pleaded guilty to the same charge earlier and will be sentenced alongside the killer.
Mr Jafferjee said Denty had "grown to despise" Mr Smith. "This defendant's attitude towards the deceased man, while in some ways irrational, may well have stemmed from the fact that Clifford had grown quite dependent on the deceased, which displeased him," he said.
"He began to manifest his attitude in a number of ways, all of which had one thing in common - a demonstration of power over the deceased. There were cruel jibes and physical threats.
"But such was the sense of duty the deceased had for his paralysed patient that even though he had expressed his fears about what was being done to him by this defendant, he continued to look after Clifford.
"This festering hostility, nurtured by this defendant, came to a head after he and others had taken Clifford to a nightclub in his specially-adapted Mercedes car-van.
"Having attended that club and as they were preparing to leave, Clifford already being placed back inside the rear of the vehicle, Curtis Smith was gunned down. He died where he fell."