Sarkozy greeted Rachida Dati back to work outside the court
President Nicolas Sarkozy has announced major changes to the French judiciary, bringing it closer to the system used in the English-speaking world.
President Sarkozy said he wanted to abolish investigating magistrates, who currently act as independent judges - a system brought in by Napoleon.
The changes would allow state prosecutors and the police to take the lead in investigations instead.
Critics say the move would leave the system open to political interference.
At present the investigating magistrate plays a powerful and independent role in certain cases, overseeing investigations by police and prosecutors, examining the evidence, and deciding if a case should go to trial.
State prosecutors, who answer to the justice minister, are now expected to take over criminal cases.
Such a change would be in line with recommendations made after a high-profile paedophilia case eight years ago - the Outreau scandal - in which more than a dozen people were wrongfully jailed following a flawed investigation by a young magistrate.
It would bring the French justice system closer to those used in much of the English-speaking world.
The government says it will speed up legal processes.
Around 100 lawyers and magistrates demonstrated on the steps of the Appeal Court, where Mr Sarkozy made his speech.
Unions representing magistrates warn the changes would compromise the independence of the French system.
Some have suggested that Mr Sarkozy is taking revenge against the independent judges who have led several far-reaching corruption probes into the affairs of leading politicians and businessmen.
Listening to the speech was the controversial Justice Minister, Rachida Dati, back at work just five days after giving birth to a daughter.