Bristol Crown Court was told that Patrick George led six men into Michael Pring's home because he believed he had burgled his flat. Mr Pring, 21, was punched and kicked and the gang, acting as 'judge, jury and executioners', watched as he fell to his death.
David Elfer, for the prosecution, said that George, 35, wanted to 'sort him out'.
The gang burst into the flat and beat Mr Pring in front of his girlfriend. He tried to barricade himself in his lounge but the gang punched their way through the door. He was cornered on the veranda and fell to his death.
Mr Elfer said: 'Men burst into the flat with George at the front who pinned Pring up against a wall saying 'you did my flat'.'
George, formerly of Aylard House, Hartcliffe, admitted conspiracy to cause actual bodily harm and was found guilty of manslaughter.
Darren Godfrey, 27, of Hartcliffe, and Raymond Mountain, 26, of Gatcombe Road, admitted the same conspiracy charge but were cleared of manslaughter.
Patrick Delaney, 26, of Briscoes Avenue, was found guilty of the conspiracy charge and cleared of manslaughter; Vincent Davis, 25, and Steven Westcott, 26, both of Hartcliffe, admitted conspiracy but were cleared of manslaughter; and Robert Gough, 25, of Hartcliffe, was cleared of both charges.
Sentence was adjourned.