All Black accused of assault in fight video
All Black accused of assault in fight videoSHARE
The 35-year-old La Rochelle lock and compatriot Romana Graham, a 31-year-old second row who left the French club at the end of last season, were involved in a late-night fight outside a club in the town last week.
"A video is being studied and will be used to discern the facts from the fiction, because it seems that everyone involved was drunk," said a police source.
Eaton, who won 15 All Blacks caps between 2005 and 2009, is one of La Rochelle's star players.
He helped the unfashionable outfit top the regular 2016/17 standings and reach the Top 14 semifinals last season.
It is the second violent incident involving top-flight French rugby players during the off-season.
Stade Francais' Fiji pair Josaia Raisuqe and Waisea Nayacalevu face trial over an alleged sexual assault and drunken violence last month.
Raisuqe, who is accused of having touched a woman's breasts, was fired by the Parisian club while Waisea has been warned and docked a pay bonus.