22 March 2012 Last updated at 16:36 ET

Boris Johnson ‘misleading the public' on robbery figures

By Esther Webber BBC News, London

The statistician said the claim was an "obfuscation of the truth"

Mayor Boris Johnson's campaign website is "misleading" the public on crime figures, a statistician has told BBC London.

The Conservative candidate for Mayor of London writes that "robberies are down 16.3%" under his mayoralty on the website backboris2012.com.

But robberies have risen 18.8% over the course of Mr Johnson's time at City Hall, according to research by independent analyst Professor Allan J. Brimicombe.

He said while more robberies occurred overall during Ken Livingstone's second term as mayor, Mr Johnson's figures obscured the fact that robberies had gone up every year since he took office.

"It's an obfuscation of the truth," said Prof Brimicombe. "He hasn't told a lie, but he has definitely put an unfortunate spin on things.

"It's about being upfront about where your statistics come from, which in this case he hasn't done."

Prof Brimicombe is a specialist in crime-mapping at the University of East London.

Burglary has also gone up - something which is not mentioned on Mr Johnson's website. A survey of Londoners by the Greater London Authority in 2011 found that burglary and robbery were the two types of crime that concerned Londoners most.

Mr Johnson defended his record, saying: "There's been a great achievement in getting crime down, and we've achieved a substantial overall reduction in the number of robberies."

He added: "That doesn't mean there isn't a problem - and with mobile phone robbery in particular. I am concerned about that."

Need for transparency

A spokesperson for Labour mayoral candidate Ken Livingstone said: "Boris Johnson says robbery is down, while the official Metropolitan Police figures are saying robbery is up.

"Last month the Tory Mayor admitted that he had cut 1,700 police officers while burglary, robbery and knife crime were all rising."

In 2011 the UK National Statistics Authority criticised Mr Johnson for misleading the public over the drop in reoffending achieved by his Heron Unit initiative at Feltham Young Offenders' Institute.

The coalition government has stressed the need for transparency in order to "empower local communities".

Home Secretary Theresa May commissioned an independent review of crime statistics last year.

The study, to which Prof Brimicombe contributed, found that there were "significant gaps" in the way crime was reported.

Elections for the Mayor of London and London Assembly take place on Thursday 3 May.