The way in which major public order events are policed "needs to evolve", a review following the disastrous handling of the G20 protests in central London has claimed.

Metropolitan police commissioner Sir Paul Stephenson ordered a review into current tactics following the death of Ian Tomlinson outside the Bank of England back in April as well as numerous complaints of police brutality.

In the second part of his review, Denis O’Connor, HM chief inspector of policing, has revealed a series of failings and claimed the shift towards more aggressive policing represents a betrayal of traditional methods used in Britain.

His report, published this morning, has identified an absence of clear standards on the use of force, variation between forces in understanding of the law and outdated training and guidance as problems which needed quickly confronting.

"The world is changing and policing needs to change with it," Mr O’Connor said.

"Public order policing needs to evolve as we move towards the London Olympics in 2012 and beyond. This will protect the rights of protestors and the wider public as well as protecting the integrity of the British policing model."

The police came in for severe criticism for the way in which the large-scale demonstrations in the capital during the G20 summit were handled.

Video footage and images of protestors being struck by batons and in one occasion struck in the face moved to turn public opinion against police.

The case of Mr Tomlinson, 47, in particular drew widespread condemnation.

Following claims the news vendor had had no contact with officers at one of the protests near the Bank of England video footage emerged showing an officer pushing him to the ground. A subsequent post-mortem gave his cause of death as internal bleeding.

Mr O’Connor warned in today’s report that other tactics – like the inappropriate use of public order powers such as stop-and-search and overt photography – raised additional human rights issues and were risking wider alienation between the police and public.

"British police risk losing the battle for the public’s consent if they win public order through tactics that appear to be unfair, aggressive or inconsistent," he added.

"This harms not just the reputation of the individual officers concerned but the police service as a whole."

While some lessons appear to have been learnt since the April protests, today’s report claims more needs to be done.

The codification of public order policing to ensure consistency of training, adoption of a set of fundamental principles on the use of force and clarification of the legal framework for the use of overt photography are all urgently needed, it demands.

Responding to the report, Chief Superintendent Derek Barnett, president-election of the Police Superintendents’ Association of England and Wales, admitted police needed to remain open-minded when dealing with major public order events.

"Where demonstrations result in violence and disorder, the public expects the police to respond in a proportionate manner to preserve the peace and prevent widespread criminality and it is important that the police service has knowledgeable, well-trained and equipped police officers who are fully accountable to the law and the public we serve," he said.

The Association of Chief Police Officers (Acpo) claimed steps were already being taken to strike a balance between facilitating protests while acknowledging human rights.

Chief Constable Meredydd Hughes said today’s report would "shape the future of public order policing".

"The service has a clear commitment to ensure peaceful protest can take place and balance the rights of everyone involved – whether taking part in protest or going about their daily business," he commented.