Former British civil servant who served as Permanent Secretary for Tax at HM Revenue and Customs (HMRC) until July 2012. Following his retirement, Hartnett advised HSBC on financial crime governance and was appointed as a consultant to the tax firm Deloitte. Gave evidence to the Inquiry on breaches of data-protection law within the Information Commissioners Office and the persistent efforts he witnessed of bogus callers trying to obtain personal details of taxpayers.