Barton was handed a suspended four-month prison sentence following a brutal attack which left Dabo with a detached retina and other head injuries.
The 30-year-old English midfielder has since joined French club Marseille, but Dabo says his ex-teammate has been spreading lies about the incident.
"He lied about what happened on training ground of Manchester City; it's amazing. It shocked me," Dabo told L'Equipe.
"There was a civil trial, he pleaded guilty and took four months suspended sentence. When he speaks, he denies he said that I am the initiator. This is false. All team members who were present during the assault testified in my favour at the trial."
Barton joined Marseille after being handed a 12-match suspension for a blowout in a game against Manchester City, which included him kneeing Sergio Aguero from behind.
"He says he is a man, a bad boy, but he is a coward. I don't want to restore my truth, but the truth," Dabo continued.
"Do not be mistaken about Barton, he is taking care of his communication. This is not the first time he does so. When he puts a knee to Aguero [during the last day of last season], he is still behind. I don't call him a man."