Principal Private Secretary to the Prime Minister appointed by Theresa May on 10 May 2017. During Tony Blair's administration, he modified the law under which the Civil Service operated to create the role of Downing Street Chief of Staff, which though held by a political advisor outranked the Principal Private Secretary. When Gordon Brown ascended to office, he reversed the change to the Civil Service law. When David Cameron became Prime Minister, he promoted the then-PPS to a new post of "Permanent Secretary, Downing Street", a position which took over heading the Prime Minister's Office. In 2012, the postholder, Jeremy Heywood, was appointed as Cabinet Secretary, this
Council of Civil Service Unions v Minister for the Civil Service While the use of the Royal Prerogative for national security reasons is considered outside the scope of the courts, most other uses of the Prerogative are now judicially reviewable in some form. The GCHQ case also confirmed that non-legal conventions might be subject to "legitimate expectation". A convention would not have usually been litigible, and it was necessary for the court to demonstrate that it was in the present case: such a rule had been established in respect of Cabinet conventions in "Attorney General v Jonathan Cape Ltd". Although the court ruled against the union, it was accepted that the