The examining magistrate, a pillar of French justice, is to be scrapped in a plan by President Sarkozy to bring the criminal system closer to Anglo-American common law.

The change, expected to be announced today, prompted an outcry from judges and left-wing politicians, who accused Mr Sarkozy of abandoning the country’s tradition of independent investigation and equality before the law. Others gave a cautious welcome to a long-debated overhaul of a system that limits suspects’ rights and has led to spectacular abuses. Though juges d’instruction now handle only serious crimes or sensitive cases, their demise would end the two-century tradition of the all-powerful super-sleuth who works in secret.

As Interior Minister in 2005 Mr Sarkozy demanded reforms after the Outreau case, in which a zealous young judge imprisoned 13 innocent people on child abuse charges. Half of them were wrongfully convicted and one committed suicide. Mr Sarkozy wants state prosecutors to run all inquiries, with a new style of independent judge acting as referee, according to Le Monde newspaper. Patrick Devedjian, a senior figure in Mr Sarkozy’s UMP party, said that the new system would give more weight to the presumption of innocence.

Critics said that suspects would now be forced to pay lawyers to mount their own defence investigation in “Anglo-Saxon style”. Mr Sarkozy was also accused of putting criminal cases under political control, because prosecutors work for the Ministry of Justice.

“This is a major step backwards for individual liberties,” said Christophe Régnard, chief of the main judges’ union. “The Government wants to settle accounts with the independent judges who have been after politicians since the 1980s.”

The institution of the juge d’instruction stems from the church courts of the Middle Ages and became the heart of the Napoleonic criminal code in 1807. The magistrate has authority to arrest, imprison, search and summons in the course of what is supposed to be an open-minded inquiry into the guilt or innocence of the defendant. Some have become household names after their dogged pursuit of politicians and financiers in scandals such as the 1990s Elf-Aquitaine corruption affair and the graft in the administration of Jacques Chirac when he was Mayor of Paris in the 1980s.

In recent decades, the judges’ powers have been trimmed and they now handle only 5 per cent of cases, involving violent crime, serious fraud, conspiracy or public figures. In 2001 the judges’ right to detain suspects indefinitely was curbed and Mr Sarkozy has already reformed procedures, getting judges to work in teams rather than in isolation.

In Anglo-American trials cases are brought with less investigation and argued from scratch in court. In France the more thorough investigation and conclusion by the judge presumes a degree of guilt that the defendant must dispel. Mr Sarkozy’s reform should change this.

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