The Home Office described the expansion of the database as a "mopping up" exercise to include DNA profiles from prisoners and offenders with mental disorders who are currently not on the database.
Denham said, "DNA profiles of a minority of prisoners and mentally disordered offenders are not on the database. We are addressing this as part of our commitment to have the DNA profiles of the known active criminal population on the database by April 2004."
The government has already committed to investing £182m in expanding the database, which currently contains samples from about 1.8 million individuals. Each month the database matches 5,000 DNA profiles taken from crime scenes with names on the system.
According to the Home Office, there is a more than 40% chance of one of these crime scene samples being matched to an individual on the database.
Updating criminal justice technology is a top priority for the government, which last year allocated £1bn to overhaul IT in the sector. In June last year a damning report from the Audit Commission said inadequate IT was contributing to delays and inefficiencies across the justice system.