Wallenda, who hails from multiple generations of high-flying daredevils, had a near fall as he stumbled on a tightrope above Baltimore's Inner Harbor earlier this year.

CNN: Daredevil completes walk across Niagara Falls

He said inner-city London had experienced the biggest drop, with Lambeth losing more than 300 officers - a fall of nearly 25% - Southwark losing 222, Lewisham losing 112 and Westminster losing 453.

BBC: London

He transformed the association's previously impenetrable inner sanctum, moving the entire operation from Lancaster Gate to new offices in Soho Square and overseeing a fall in the average age of staff from 55 to 32.

BBC: Profile: Adam Crozier