Undercover policing operations should have to be authorised in advance by a judge, the head of the Association of Chief Police Officers (Acpo) has said.
Sir Hugh Orde, Acpo president, said the change was needed to restore public confidence.
It follows concerns about the role played by ex-Metropolitan Police constable Mark Kennedy, who spent a reported seven years posing as an environmental activist.
Sir Hugh said the benefits of judicial oversight of future operations would “far outweigh the additional administrative burden”.
Speaking at a policing seminar held by human rights group Liberty in central London, Sir Hugh said: “The current system of retrospective inspection is, in my judgment, no longer sufficient to secure the confidence of right thinking people that such interference with citizens’ rights (with its foreseeable collateral intrusion on many) is appropriate.
“Therefore the solution must take the form of some independent pre-authority that is already a common feature in other areas of policing in this country.”
Control of the National Public Order Intelligence Unit (NPOIU), to which undercover officer Mr Kennedy belonged, was transferred from Acpo to Scotland Yard last Monday.
Six protesters accused of planning to invade Ratcliffe-on-Soar power station in Nottinghamshire claimed prosecutors dropped charges against them after Mr Kennedy offered to give evidence on their behalf.
Several inquiries – by Her Majesty’s Inspectorate of Constabulary (HMIC), the Independent Police Complaints Commission (IPCC), the Serious and Organised Crime Agency (Soca) and Scotland Yard – are investigating aspects of undercover policing in the wake of the controversy.
Liberty director Shami Chakrabarti said: “Recent revelations of abusive infiltration into non-violent protest movements should shame every democrat in Britain. We agree with Sir Hugh that such an important service should be accountable not to politics but to the law.”