Joining the Cabinet brings with it individual responsibilities to perform and run their departments or portfolio to the satisfaction of the Prime Minister.“They are responsible for the actions, successes and failures of their departments.” If they do not perform they may be ‘shuffled’ into another ministerial slot as part of a cabinet reshuffle, demoted to a more junior position or dropped completely and returned to either the back benches of the House of Commons or to the House of Lords.
It also brings responsibilities as a ‘collective’. Through the Ministerial Code, decisions made by the Cabinet are binding on all members of the Government. This means that even if you disagreed with a course of action privately in the meeting you must follow the decision made by the majority, and do so publicly, or otherwise resign. An example of this was Robin Cook who whilst in Prime Minister Tony Blair’s government felt that he could not support the decision support the invasion of Iraq. He therefore resigned.The perceived benefits of this are that it keeps the Government united (particularly in the eyes of voters) and prevents confusion around policy, as even if you don’t like it everyone knows what needs to be done.
It is not unknown however for Ministers to use other means to make their feelings known, whilst supporting something publicly, through an intermediary and into the media.