The cousin of one of the men convicted of killing City lawyer Tom ap Rhys Pryce has been jailed for murder
Lloywen Carty was found guilty on Tuesday of being part of a gang who shot Lee Subaran, 27, at a party after the 2004 Notting Hill Carnival.
Last month, his cousin Donnel Carty, 19, was given a life sentence for killing Mr ap Rhys Pryce, 31, in Kensal Green, north-west London, in January.
An Old Bailey judge ruled Lloywen, 26, must serve at least 30 years in prison.
Lloywen Carty was with about a dozen members of the drug-dealing Mus Luv Crew gang who surrounded Mr Subaran and his brother Tyrone at a street party, the court heard.
The victim, from Mill Hill, north London, was shot at point blank range in the neck and chest after being accused of showing disrespect to gang member Leon Roberts.
Detectives believe up to six guns were drawn during the incident and bullets were fired from at least three, including a MAC 10 machine gun.
Judge Stephen Kramer praised police for their investigation into the Mus Luv Crew gang on which the case focused.
He said: "Whatever the motive was for this cold-blooded execution, he did not deserve that death."
Conroy Smith, 29, a kitchen assistant of Harlesden, north London, and Jermaine Labastide, 28, a music promoter, of Kennington, south London, were also found guilty of murder.
They were both jailed for life and ordered to serve at least 30 years in prison.
Other gang members, Leon Roberts, Tafari Dacas and Shane Taylor, were convicted and jailed for life in another court case last year.
The Cartys were both living with their grandfather in Burrows Road, Kensal Green, north London, in January when Mr ap Rhys Pryce, 31, was stabbed by Donnel and Delano Brown, 18.
Brown and Carty were given life sentences, with a minimum jail term of 21 years.
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