It is a constitutional truth that civil servants advise, but ministers decide - see my article for the Telegraph

In 1854, two officials, Sir Stafford Northcote, and Sir Charles Trevelyan produced their report which transformed our civil service to become permanent, impartial and appointed on merit. 

Since then, it has had to adapt to universal suffrage and popular democracy, to the progress of science and society, and to all that history has thrown at it. 

Read more here.