Database of murderers and rapists goes live

A database that will give police and probation officers information about the 500 most dangerous freed offenders in London begins operating this month.

The ViSOR system contains 46 different pieces of data about each convict, ranging from their names, aliases and addresses to details of their methods of committing crime.

It also includes descriptions of distinguishing marks such as tattoos as well as offenders' previous convictions, licence conditions and risk to the public.

The convicts include murderers, rapists and other violent offenders who have completed their prison sentences but remain a threat.

The aim of the database is to help probation staff monitor criminals and prevent a repeat of the mistakes such as those in the case of murdered City financier John Monckton, where information on offenders was not passed between different law enforcement bodies.

Police forces already use it to help them keep track of sex offenders.

Each convict's details will be kept on the database for 100 years and updated whenever new information, such as a further offence or a new address, becomes available.

Anne Williams of the London probation service said: "This system will contain very detailed information about 500 higher-risk cases and will be invaluable for supervision and detection."