There have been a number of inquiries into the causes of the riots that took place last August: the Guardian and LSE's research Reading the Riots; the government-commissioned riots panel and, locally in Tottenham, the citizen's panel and the community panel carried out extensive investigations into the causes of the riots. Between them they have interviewed hundreds of people who were caught up in the events. They have all concluded their investigations and made their recommendations.

How different the IPPC investigation into the initial incident that led to these disturbances, the shooting of Mark Duggan in Tottenham on 4 August 2011. Nine months into the investigation the Independent Police Complaints Commission has still not been able to interview the officers involved in the operation that led to the shooting. None of the 31 have agreed to talk to the IPCC over their role. Each officer has, apparently, given a statement but has declined to be interviewed by the very body charged with carrying out a full and robust investigation into their actions.

As a result, the IPCC this week called for the power to demand witness evidence from officers. Currently it can only demand that officers give an interview if they are suspected of having committed a crime. The family of Duggan, and everyone else I have spoken to about this in Tottenham, including senior police officers, support the IPCC's demands. It is inconceivable to most people that these officers have not been required to give a full and transparent account of their actions. Mark's family believe this is the very least they should expect from those whose duty it is to protect and serve.

Lest we forget, in addition to Mark, five lives were lost in those four crazy days in August. Towns and cities were turned into battle zones, and 4,000 people have since been arrested, over half of them incarcerated. Estimates suggest that up to 15,000 people were on the streets, either as rioters or onlookers. All of this because of the actions of these 31 police officers, yet they refuse ? and are steadfastly supported by Acpo and the Police Federation ? to attend interviews that could show whether they acted properly.

The truth is that they are concerned their words might be used against them; that they will say things that will implicate themselves or their colleagues. However, in this case the police chose a location to stop the cab, in which Mark was travelling, where there was no CCTV coverage; they are also alleged to have chased away onlookers, so they are the only witnesses to these events. This surely calls for a change to the law, which allows them to obstruct the IPCC investigation.

In addition, there are the laws that allow for telephone intercept evidence to be withheld from a coroner ? another issue that has been thrown up in this investigation, and another possible barrier to the full facts ever being made public.

In effect we now have a situation where we cannot be told what information the police had received to make them follow Mark. The officers who do know and were at the scene do not have to answer the IPCC questions.

So, as the law currently stands, you could go to a police conference, with hundreds of officers in attendance. If an officer shot you in front of the entire audience not one of them would be forced to give a statement. Yet, if you were to shoot one of them, the entire audience would be ready to testify against you.

It is right that, as a society, we do not simply seek to hang out to dry those whose job it is to protect us, but these are clearly double standards. If policing is to be by the consent of the people, then it is critical we have total faith that every officer will be held totally accountable for his or her actions.

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