Damian Rzeszowski showed no emotion in the dock as the presiding judge, Sir Michael Birt, read out the verdicts that two jurats - similar to magistrates in the UK - had reached.
Throughout the trial, the defendant had constantly stared down at the floor, not looking up at any time.
No members of the victims' families were in court, but the public gallery was full of curious onlookers.
Judge Birt, who is the Bailiff of Jersey, said Rzeszowski would be sentenced on October 29.
More top news
The former Top Gear also revealed his cancer scare just two days before the fracas which led to his sacking.
Tonight will start off clear in many areas, but cloud will increase from the east overnight, bringing some light and patchy rain.
Defending champions Arsenal squeezed into the FA Cup final despite a spirited fightback from Reading, who forced extra-time