It has been a significant week – but Tunisia's justice system lacks independence and the principle of 'command responsibility'

A few years ago Zine el Abidine Ben Ali looked set to be president of Tunisia for life, having ruled since 1987. Instead, on Wednesday, a Tunisian military court sentenced him to prison for life, for complicity in the murder and attempted murder of demonstrators during the revolution that began the Arab spring.

In practice, this seems likely to mean exile for life in Saudi Arabia, the country the 75-year-old former ruler fled to with his family after the deaths of more than 100 protesters failed to stop the popular uprising.

The two trials that concluded on Wednesday were far from ideal, even if several of his most senior officials were convicted, and some acquitted. Ben Ali's absence from Tunisia meant his trial was conducted in absentia. So for him justice has still not been served, although all of his co-defendants were present.

If he did ever return to the country he should be entitled to a new hearing. There appears little chance of that at present, with the current Tunisian government making only the most desultory requests of the Saudis. The Tunisian prime minister has said the issue of Ben Ali's extradition is "minor".

The trial also took place in a military court, which automatically raises concerns about independence. Military justice should be limited to prosecuting military personnel for strictly military issues, and trials for killing civilians belong in ordinary courts.

Although significant reforms in military justice took place after the revolution, bringing in some civilian judges and allowing the victims of crimes to participate in trials as full parties, problems remain. A senior civilian judge told me in Tunis a few weeks ago: "The military judges now wear robes, but underneath they still have their uniforms and their ranks" – meaning that the judges are still subject to military hierarchy. The defence minister still appoints military judges.

Despite these problems, what is going on in Tunisia should be recognised as significant. It was not just Ben Ali who was convicted on Wednesday but several other senior figures, including his former minister of the interior Rafik Hadj Kacem. And although the lawyers for the victims and the defendants did appear to have well-founded complaints about their ability to access some of the evidence, in our monitoring of the hearings we found little evidence of serious violations of the right to a fair trial. Indeed the court acquitted others, including Ali Seriati, former head of the presidential guard, to the great disgust of many. But the prosecution had not presented evidence that Seriati or his forces were present during the relevant shootings, or that he gave orders to shoot demonstrators.

In fact the greatest problem in ensuring legal accountability of senior people is that Tunisian law does not recognise the principle of "command responsibility" – that those in positions of authority can be criminally responsible for serious crimes committed by their subordinates, when they knew or should have known about the crimes and failed to prevent them or punish those responsible. This is a basic principle of international criminal justice, and has shown itself again and again to be essential in holding to account the most senior officials – those who are rarely at the scene of a crime and do not give their orders in writing. Without this principle in Tunisian law the prosecution has had to try to show that the senior figures actually gave orders.

Tunisia has dropped from the headlines, often for good reasons, as it has not experienced the chaos of Libya or Egypt. Yet it remains at a critical stage, with its first elected assembly in the process of drawing up a new constitution. At the same time the status of justice, and basic rule of law remains a critical signal of whether it is progressing toward the country the demonstrators against Ben Ali wanted. Tunisia has the world's only minister for transitional justice, but there appears to be very slow progress on the basic issues that need to be addressed in reforming justice after a revolution.

Tunisia needs to make the justice system fully independent of the government – a system in which ministers do not interfere in prosecution decisions or trials. But Tunisia also needs to remove, and even prosecute, the judges who were clearly complicit in the abuses under Ben Ali. At present a "temporary" solution, of suspending the Ben Ali-era mechanisms of governing the justice system, has given the justice minister more power to appoint, discipline and assign judges than ever before. Such a temporary situation should not become permanent.

Justice in Tunisia remains in flux. You still have to step over barbed wire and walk past an army vehicle to get into the main civilian court. The trials of senior figures show a certain willingness to attempt to address, in court, the crimes committed by the most senior people. But the laws and justice system are still not up to the task of such prosecutions. It is now urgent for Tunisia to reform them to meet the international standards it has signed up to, not least to recognise command responsibility for serious crimes, and ensure the independence of the judges and prosecutors from politicians.

*Clive Baldwin is senior legal advisor at Human Rights Watch.*