They cite the case of Rachid Ramda, an Algerian exile currently in prison in Britain, who is appealing against a court decision that he should be extradited to France. The French claim that he is an organiser and treasurer of the 1995 bombing campaign and resent what they see as British reluctance to hand him over.
Claims have come to light, however, that appear to cast serious doubt on the quality of French justice as it applies to Muslims detained in connection with terrorist or extremist offences. An open letter from detainees held at the Fleury-Merogis prison accuses the authorities of discrimination, severe maltreatment, religious persecution and psychological pressure.
"We Muslim prisoners, labelled 'Islamists'," the handwritten document said, "have decided to break our silence and bring to public notice ... the excesses to which we have long been subjected."
There follow seven specific allegations. They include what is described as the "Machiavellian methods" of the police in manufacturing, planting or destroying evidence; physical maltreatment - including beatings of prisoners and sleep deprivation - and the intimidation of detainees' families who are held or called in for questioning without the statutory warrant.
Some police officers are accused of forcing Muslim prisoners to commit acts of "blasphemy", such as "stamping on the Koran", while others are said to have warned prisoners that they will be marked men after their release. "One officer told one of us: 'When you get out of prison you will be a dead man'."
The majority of allegations concern the Police Judiciaire - the main criminal investigation branch of the police - but others are also implicated.
Individual doctors are accused of issuing false medical reports to cover up the results of beatings, and journalists, "with rare honourable exceptions", are accused of hushing up what is going on and broadcasting "film of arrests that violates the confidentiality of legal investigations".
The prisoners also protest about the use of informants, confessions extracted under duress and complicity between certain lawyers and magistrates.
They claim that electronic tags are unlawfully attached to prisoners during transfer, and that prisoners are subjected to repeated strip-searching and are regularly "roughed up and humiliated".
In an allegation that is particularly pertinent to the Rachid Ramda case, they say that prisoners are held for very long periods "sometimes illegally" without charge, and that there are some who have spent more than a year in Fleury-Merogis prison "after extradition from other European countries who have still not been questioned".
A spokesman for the Police Judiciaire, which is subordinate to the Interior Ministry, dismissed the allegations as "old" (the open letter is dated 31 October) and said he found them "not very credible ... without much foundation".
The fact that they had not been reported in the French press, he suggested, showed that they were "generally not taken seriously". Specifically on the period of time prisoners are held without charge, another police source said this was due to the "particular nature" of the French justice system.
He said he was familiar with the letter and had seen earlier, more virulently worded protests as well. In all cases, he said, the allegations were too unspecific to warrant an inquiry. If a named individual had made a specific complaint, he said, this would have been investigated, but no such complaints had been received. In other words, as far as the police are concerned, there have been no investigations because there have been no complaints.
One of the charges in the prisoners' letter, however, is that the authorities try to prevent information about the plight of Muslim prisoners from coming to light.
In France, where the interest of many civil liberties groups tends to stop at the prison gate and where anyone in jail (especially if thought to have Islamic connections) is already guilty in the public mind by association, such an information gap can be sustained more easily than in the United Kingdom.
Fears about the effect of the bombings on elementary civil liberties first arose after the introduction in Paris and other cities of the quasi- military state of alert, Vigipirate, in the summer of 1995.
Hundreds of young men of North African appearance were summarily stopped and searched each day. Those without valid papers were detained. There were dawn raids on housing estates in which dozens were held. Many were released without charge, days or weeks later.
Many others, however, were not so fortunate. No one has yet been charged either with the 1995 bomb attacks or the attack last December at Port Royale metro station in Paris.
The Muslim prisoners of Fleury-Merogis claim that French justice works at different speeds: "One for Corsicans - dialogue and firmness [wheeling and dealing]; another for Basques - political and judicial barter with Spain [exchanges of Basques for Islamists]; a third for Kurds - somewhere in between; and a fourth for Muslims - persecution, hatred and repression without end."