Scotland Yard is to review its policing of violent demonstrations after the G20 protests to see if London needs harsher, European-style methods that could include the use of water cannon.

Sir Paul Stephenson, the Commissioner of the Metropolitan Police, said that they would look at the more robust tactics used by other European police forces.

In an interview with The Times to mark his first 100 days in office, Sir Paul also said that a failure to merge smaller police forces had left many unable to cope with serious and organised crime.

Sitting in his large, corner office at Scotland Yard, Sir Paul admitted that he had had a “tricky” start as commissioner after publicity surrounding the incompetency of officers involved in two rape trials and the policing of the G20 summit, which was followed by the death of Ian Tomlinson, a newspaper vendor.

The public dismay over the policing of the demonstration has led to four separate investigations by the Independent Police Complaints Commission into allegations of police brutality. Sir Paul has also called for a review of public-order tactics by Denis O’Connor, HM Chief Inspector of Constabulary.

The Met was also criticised for containing demonstrators for hours with its controversial “kettling” tactic.

Sir Paul said that he wanted to “recognise the disquiet over our tactic without actually saying the tactic is wrong”. He said that letting demonstrators leave the area when they wished and frightening members of the public was “hugely irresponsible”.

“Is this the price we pay for not having the paramilitary equipment that our colleagues would have on the Continent?”

Asked if he would consider using the same methods as deployed by European police forces, which include the use of water cannon, the commissioner said: “I would be reluctant. I don’t want to see that development but let’s commission a review.” In September 2005 the Met hosted a demonstration of water cannon although Sir Paul’s predecessor, Sir Ian Blair, said that he was not persuaded of the merits and that it would mark a “significant departure” from policing tradition in London.

Six years ago Sir Paul wrote a paper recommending that smaller forces around the country be merged. He said that he was disappointed that nothing had been done to improve the situation after the plan to amalgamate some forces was abandoned in 2006.

“If amalgamation is not going to be the solution, what is going to be the solution? That is the issue.” Asked what he thought the solution was, he said: “I gave my view in 2003,” but it was up to Parliament to decide.

Describing himself as a “fuddyduddy”, he said that modern officers were not smart enough and he “hated fashionable stubble”.

“Most organisations want their people . . . to look smart. It’s right and proper they want them to look smart.”

But Sir Paul admitted that he was no style guru. “What is the right length of a beard? I don’t know. I am horrified at being asked to judge on those sort of things.”

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