The Convention of collective cabinet responsibility emphasises the unanimity of government and its accountability to Parliament. Bagehot in 1887, called the cabinet the most powerful body in the nation (The English Constitution, 1963) and collective responsibility meant every member of the cabinet had the right to take part in cabinet discussions but was bound by the decision eventually reached.
In contrast, John Mackintosh (The British Cabinet,1977), wrote; The principle policies of a government may not be and often are not originated in cabinet. Michael Heseltine, in the aftermath of the Westland affair in 1986, said there had been a breakdown of constitutional government and that the Prime Minister had frustrated collective responsibility for the Westland issue, suggesting conventions governing the Cabinet were in decline….(short extract)