A 22-year-old has been found guilty of manslaughter after he punched his childhood friend, causing fatal injuries, while out celebrating his 21st birthday.
Patrick Conway, of St John's Road, East Molesey, admitted one count of violent disorder after his involvement in a mass brawl in Teddington on November 10, 2012, which ended in the death of 20-year-old student Patrick Lawless.
He denied manslaughter, but the jury at Kingston Crown Court found him guilty after a five-week trial.
The jury was told he punched Mr Lawless in the head in Field Lane, Teddington, and caused him to slump to the floor. Mr Lawless died several days later in hospital.
Footage from an iPhone was played in court that showed the fight outside the Royal Oak pub in Teddington.
Witnesses recounted seeing a "mini riot" as the 30-man brawl unfolded in sleepy Teddington High Street.
Six other men faced charges relating to the violence.
Max Mears, 19, of Temple Sheen Road, SW14 and Callum Hurley, 20, of Fulmer Close, Hampton, were both found guilty of violent disorder.
Aaron Noonan, 21, of Brick Farm Close, Richmond, Ben Axelrod, 26, of Station Approach, Epsom, and Edward Thompson-Membury, 22, of Pollard Street, London, were all cleared of violent disorder.
Inigo Anderson, 22, of Queenswood Avenue, Hampton was found not guilty of assault causing actual bodily harm.
James Hales, 22, of Rectory Grove, Hampton Hill pleaded guilty at an earlier hearing to two counts of grievous bodily harm and one count of violent disorder.
Detective Inspector Will Reynolds, who led the investigation, said: “It is almost incomprehensible how a 21st birthday celebration can end in such tragic circumstances, with Patrick Lawless being punched by his childhood friend who delivered the fatal blow.
“These tragic circumstances were the result of the toxic combination of drinking, drug taking and male bravado and the jury rightly decided that the events that began in Teddington High Street that night were disgraceful and unlawful.
“These convictions are a reminder to those who have been found guilty that their decision to engage in drunken violence in full view of members of the public means they are now being held accountable for their actions.”
The men are due to be sentenced on April 16.