With a new term stretching ahead of it, what should the new government be doing to protect civil liberties and to promote human rights. In a series of articles Deborah Clark, the Director of Public Affairs at Liberty, will look at areas of the Criminal Justice System where new laws, reform, or review are needed. In this issue she looks at the need to improve investigations into deaths in custody.

Since 1990, figures compiled by the campaign group Inquest show, there have been 551 deaths in police custody and 992 deaths in prison custody. Although the numbers dying in police care are falling (from a high of 65 in 1998, to 41 in 1999 and 27 in 2000), the trend of numbers of deaths in prison is upward: with 117 deaths in 1997, 134 in 1998, 146 in 1999, and 142 in 2000.

The 1998 figures were described by the Police Complaints Authority (PCA) as 'the largest number of deaths in police care or custody on record.' The decrease since is in part due to PCA initiatives. However the number of deaths clearly remains a cause for concern, and there are still widespread misgivings about their follow-up and investigation.

These figures include all deaths - including those due to illness, suicides and deaths caused by the actions of other prisoners, or the action or negligence of officers. Establishing a clear explanation of the circumstances is important in all cases. Article 2 of the Human Rights Act creates a positive duty on the state to protect life. Where people die at the hands of state institutions, the circumstances must be fully and openly investigated. The present investigation procedures for deaths in custody and instances where excessive force has been used have been widely criticised, yet there is very little information on how the system as a whole could or should be reformed.

A key concern is the ability of the judicial system, primarily through the inquest procedure, to provide an explanation of what has happened, accountability and redress. In particular, where police practices are involved in the death, there is a potential conflict between the role of the police as custodians of victims, investigators of deaths in custody, and potential suspects. To an extent, a similar conflict of roles can hamper accountability and investigation mechanisms for deaths in prison custody, immigration detention, mental health custody and so on.

The Home Office recently announced a wide-ranging enquiry into the coroners' system. This will provide an opportunity to consider these issues of investigation and accountability - to ensure that lessons from individual deaths are learned across the custody system. To find solutions that work for all types of controversial deaths, and in particular those in prison, it needs first to concentrate on the process that follows deaths in custody.

It is crucial that any investigation is conducted in an open and transparent manner to ensure confidence in the system. As well as dealing with the needs of friends and family of the deceased, the system must provide a fair and thorough investigation, protecting the rights of officers and others under suspicion. Finally, it is equally important that any lessons learned are effectively highlighted and communicated to all of the relevant bodies.

Deaths in custody are traumatic for all involved - the custodians of people detained as well as the victims' relatives and families. We need to have some clear ideas how we can best prevent such tragedies in the future. An improved investigation process would help generate improvements across the custody system: Liberty will want to work closely with the proposed review of the coroners' system, and to suggest alternative mechanisms to investigate deaths in custody.