I’d worked alongside Ian [Metropolitan Police Commissioner Sir Ian Blair] when he was deputy to Sir John Stevens. He was brilliant in that role. He made things happen: he delivered a new IT system across the Met and drove forward an anti-corruption agenda.

I considered him a friend. When I became chief constable of Norfolk we kept in regular, though not frequent, contact, and when he became Commissioner I was delighted when he brought me on to his management board as Assistant Commissioner for Specialist Operations.

Over time, though, I believe he became distant and aloof. I often discussed my perception of him with my colleagues and learnt that others shared it.

It was so frustrating: we all wanted him to succeed, but I believe that he became so isolated from some in his top team that he did not seem to notice he risked making dangerous enemies.

When he resigned in 2008 because the Mayor of London didn’t fully support him, I did not see many senior colleagues stepping in to take his side. Ian’s departure was dreadfully sad not only for him and his family but also for the Met. He earned the reputation of being gaffe-prone, and by the end he didn’t have a hope in hell of shaking it off.

Ian had got the top job in part on a streamlining ticket and had planned to cut and redistribute budgets, enabling him to put more bobbies on the beat. To achieve this he commissioned a review to help him restructure and modernise the Met.

At first the level of savings he intended was manageable. Five months down the line it became clear the objective was still correct but that some of the detail would have to go. Unforeseen circumstances got in the way.

The 7/7 bomb attacks led to the biggest criminal investigation in British history and we lost all control of the budget. They turned out to be just the start: later, we had a copycat set of bomb attacks to deal with, we killed an innocent man, mistaking him for a suicide bomber, and we carried out a mass raid on a house looking for bombs and got nothing but trouble.

Despite all of this, we were still ploughing on with budget cuts and restructuring without grasping that things around us were crumbling. It was crazy. I still wonder why I didn’t say, “What are we doing?” It would have been sensible for Ian to renegotiate the objective with the chairman of the Metropolitan Police Authority (MPS) and tell him publicly that the cuts were no longer achievable.

Instead, senior officers were pitted against one another as we fought for diminishing funds. It wasn’t personalities or people that were the problem. It was the budget. We should have been putting all our energies into fighting terrorism, but my colleagues and I wasted precious hours in surreal debates because the Met had committed to cuts it couldn’t cope with.

Not only had Ian agreed cutbacks, he had committed to increasing the number of bobbies on the beat. He had pledged that every one of the 624 wards in London would get a dedicated neighbourhood team and they would be available for their beat 24/7. So, we had to reduce budgets and put more police on the streets. But who or what would pay for them?

I could be accused of being smart after the event, but much has been learnt from that period — you need to keep your top team on board and be ready to change direction completely if something, such as 7/7, strikes out of the blue. When something happens that hadn’t been anticipated and has a profound effect on the initial planning, you must say, “Whoa! Time out. Let’s reassess”.

We muttered our concern in the corridors but, despite our macho airs, some of us didn’t have the strength of character to say no.

To me, this situation was inextricably linked to another distraction from the job of tracking terrorists: the increasing politicisation of policing. On Ian’s watch, as he pushed through his ward-based policing plan, politicians became increasingly involved in deciding how London was policed.

Ironically, politics eventually brought Ian down when Boris Johnson made clear he did not have full confidence in the Commissioner and Ian felt obliged to resign.

The replacement of Ian with Sir Paul Stephenson in 2009 came with signals that the new commissioner was not going to be a celebrity cop. He would have a new style, with a strong focus on basic policing.

However, if I was in Sir Paul’s position, with Boris Johnson at the helm of the MPA, I wouldn’t be so certain that politics would not once again rear its ugly head. In fact it’s already beginning to happen.

— Terrorist Hunters by Andy Hayman with Margaret Gilmore is published by Bantam Press. RRP £18.99 and offer price £17.09. Books First: 0845 2712134 or visit timesonline.co.uk/booksfirst

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