The report said match officials were the fourth most targeted group, surpassing finalists the All Blacks.
Barnes was the single most targeted individual throughout the tournament (inclusive of players, match officials and individual stakeholders). He received a third of all abuse targeted directly at individuals.
The abuse towards match officials ranged from match-fixing and corruption accusations to violent and family-related threats.
An example of the abuse towards Barnes said: “You ******* idiot, I hope your wife dies in a car accident and your kids taken away from you due to alcoholism and finally come to your senses and kill yourself.”
According to the report, 21 verified social media accounts based in New Zealand sent abuse during the tournament. The most verified accounts originated in France (95) and South Africa (71).
The largest spike in abuse came after France was narrowly knocked out of the tournament by South Africa in the quarter-finals. Kiwi Ben O’Keeffe was in charge of that game.
A further spike was seen on the day of the final between the All Blacks and the Springboks due to the profile of the game – and close result. The majority of abuse was targeted again at Barnes, over the players or teams.
England was the most targeted team followed by the Springboks, France and the All Blacks. South Africa was also targeted with high volumes of abuse, elevated by beating New Zealand in the final.
Last year Barnes opened up on the abuse he has received during his career, saying social media abuse is getting worse.
Barnes announced his retirement from refereeing last year, stating that online abuse and threats have become too regular for everyone involved in rugby.
In an interview with the BBC, Barnes said threats towards his family crossed a line and that online abuse is getting worse.
“When people make threats against your wife and kids, they should be held to account and punished.