Detective Superintendent John Jones is the former head of Operation Dalehouse, an anti-Yardie and crack initiative in south London, which was wound down last year despite considerable success.
During the second year of its operation, there was only one drug-related murder in south-east London; this year there have been at least four before the death of PC Dunne, as well as countless shootings.
In one murder, a man who had twice been deported and still found his way back, died in a hail of 15 bullets fired from three guns.
Although a quantity of cannabis was discovered at the house where the murder which attracted PC Dunne's attention occurred - and the victim was under surveillance by local drugs squad officers - Scotland Yard said that it could not confirm the presence of crack.
Much of the crack-related violence is committed by Yardie gangs - criminals from Jamaica who have become involved in cocaine distribution at the behest of the Colombian cartels, anxious to increase their operations in western Europe.
Many Yardies enter Britain as illegal immigrants and move around frequently in order to stay one step ahead of the police.
Senior Scotland Yard officers have replaced Dalehouse with a series of London initiatives, including an intelligence gathering exercise headed by Commander John Grieve, head of the Yard's criminal intelligence department.