The head of the official statistics watchdog has reprimanded Boris Johnson and the Home Office for incorrectly saying crime has fallen by 14%, when this excludes the fastest-rising category of crime. Sir David Norgrove, the head of the UK Statistics Authority, said he would be writing to the offices of Johnson and Priti Patel, the home secretary, to highlight what he called a “misleading” use of statistics. Replying to a letter about the claims from Alistair Carmichael, the Liberal Democrat home affairs spokesperson, Norgrove said Johnson and Patel had been incorrect to claim that crime was falling. A Home Office press release from last week twice “presented the statistics to give a positive picture of trends in crime in England and Wales” between June 2019 and September 2021, but did so by not including fraud and computer misuse, he wrote. “The exclusion was stated. However, in the title and in two other places the release refers to a fall in crime, without making clear that this is true only if fraud and computer misuse are excluded,” the letter said, Speaking in the Commons on Monday, Johnson said the government was “cutting crime by 14%”, a reference to statistics between September 2019 and September 2021. This also excluded fraud and computer misuse “though the prime minister did not make that clear”, Norgrove wrote. He said: “If fraud and computer misuse are counted in total crime as they should be, total crime in fact increased by 14% between the year ending September 2019 and the year ending September 2021. The ONS bulletin quite properly includes fraud and computer misuse in total crime.” Fraud and computer misuse offences have climbed significantly during lockdown and other Covid restrictions, while other offences such as theft have dropped. Carmichael called it “a damning verdict from the official watchdog”. He said: “When the government’s record on crime is so bad that both the prime minister and home secretary feel the need to fiddle the figures, it is clear we need a new approach. “The prime minister must come before parliament to apologise for his latest lie and set the record straight.” The government has been approached for comment.