The human-rights group, Amnesty International, has accused the French authorities of failing to investigate alleged violence by security forces, BBC reported.
Allegations of beatings, and even unlawful killings, were rarely looked into and those responsible seldom brought to justice, Amnesty said.
In a report, it cited cases of abuse, many involving ethnic minorities and foreign nationals living in France.
French officials denied that any degree of police violence was being condoned.
David Diaz-Jogeix, the deputy director of Amnesty International's Europe and Central Asia programme said: "In a climate where police abuse can go unchecked, the de facto impunity of law enforcement officials in France is unacceptable."
"Victims, many of whom are French citizens from an ethnic minority or foreign nationals, are all too often left without justice."
Amnesty admitted that "not every complaint made against the police has merit", but added that the discrepancy between the number of complaints made and the number of disciplinary sanctions "raises questions about the thoroughness and impartiality of the investigations".
A high number of complaints against law enforcement officials were closed by the prosecutor without reaching trial, the report said.
Guillaume Didier, a spokesperson for the French justice ministry, rejected the accusation.
"There is no tolerance for police violence," he told the AFP news agency. "There are systematic criminal inquiries. Police officers have neither more nor fewer rights than other defendants."
The interior ministry said: "No police officer is above the law."