The files on the 1996 killing of Sophie Toscan du Plantier have been handed over to the French embassy in Dublin.
Ms Toscan du Plantier was found beaten to death on 23 December 1996 in Co Cork. She was 39.
Minister for Justice Dermot Ahern said he hoped the file handover would help the victim's family in their long-running fight to bring the killer to justice.
He deeply regretted that no one had ever been charged with her murder.
‘I've taken a deep personal interest in bringing about this situation so today I am satisfied that at least this step has been taken in the effort to secure justice,’ he said.
Mr Ahern said the police investigation remains open and every lead would be pursued.
Gardaí pledged full assistance to the French authorities last July after the Director of Punlic Prosecutions indicated there was no immediate prospect of charges being brought.
Last June, a French judge ordered that the body be exhumed and a new post mortem was undertaken at the request of her family.
Her body, in nightclothes and wearing boots, was discovered by a neighbour on an isolated lane leading to her holiday home.
A preliminary inquest was told she had suffered severe head and facial injuries which had been caused by a blunt instrument. No murder weapon was ever found.
Ms Toscan du Plantier’s parents, Georges and Marguerite Bouniol, visit the lane where she was found every year on the anniversary of her death.
The spot is marked by a small stone Celtic cross inscribed ‘Sophie’.