Gordon Brown has called in an established standards watchdog to police a new code on ministerial behaviour as part of a series of changes aimed at restoring trust in the way that Britain is governed.

The Prime Minister is also to give up his powers over a series of appointments including the Archbishop of Canterbury and judges.

Sir Philip Mawer, the current Parliamentary Commissioner for Standards will become the first Independent Adviser on Ministers’ Interests. Sir Philip, who has proved a tough enforcer of MPs’ conduct over the past five years, will oversee the publication of a report listing ministers’ outside interests as well as investigating alleged breaches of the rules.

Former ministers wanting to take up posts in the private sector will for the first time be required to abide by the decisions of an independent commmittee on business appointments in another tightening of the rules. The Government will also bow out of its role in appointing bishops in the Church of England in one of the biggest changes to the relationship between Church and State for generations.

The Prime Minister made it clear, however, that the Government remained committed to the establishment of the Church of England with the monarch as Supreme Governor.

In a separate proposal, senior judges could also be approved by Parliament under American-style reforms outlined by the Prime Minister yesterday.

Mr Brown said he wanted to remove the Lord Chancellor’s remaining residual powers over the appointment of judges. Instead, the Government is “willing to look further” than the present system, “including conceivably a role for Parliament itself, after consultation with the the judiciary, Parliament and the public”. Judges would firmly resist any move towards US-style “confirmation hearings” with candidates questioned on everything from their politics to their hobbies.

Candidates for other public appointments, however, might have to submit to cross-examination by MPs. Since ministers have ultimate responsibility for about 21,000 posts, only the most senior appointments will be subject to the new hearings. The list has yet to be finalised but is likely to include posts such as the Chief Inspector of Prisons and the Health Service Commissioner.

In yesterday’s constitutional Green Paper, the Government says the Prime Minister should no longer use the royal prerogative “to exercise choice in recommending appointments of senior ecclesiastical posts, including diocesan bishops, to the Queen”. The paper says the Prime Minister should not have “an active role” in the selection of candidates.

At present, the Church of England chooses two names for diocesan posts, including that of Archbishop of Canterbury, and presents them to the Prime Minister in order of preference. The Prime Minister has the power to choose the second name, or ask for more names.

From now on, the Church’s Crown Nominations Commission should put just one name to the Prime Minister, who would then convey this recommendation to the Queen.

Church leaders welcomed the change. The Archbishop of York, Dr John Sentamu, said: “The Prime Minister and the Secretary of State for Justice consulted me about his intentions which I believe accord with the declared wish of the Church of England. I welcome the prospect of the Church being the decisive voice in the appointment of bishops which the General Synod called for 33 years ago. I am grateful for the Prime Minister’s thoughtfulness and for his overt support for the role of the Queen and the establishment by law of the Church of England which have been strongly reiterated in the Green Paper.”

The Church will also discuss with Government the way other senior appointments, such as cathedral deans are made. The subject is to be debated at the next General Synod meeting which opens this weekend in York.

However, the leader of the Roman Catholic Church in Scotland, Cardinal Keith O’Brien said: “I am deeply disappointed at the statement from Gordon Brown. I remain deeply concerned that the Act of Settlement will continue to exist and believe it constitutes state-sponsored sectarianism.

“I wrote to Gordon Brown in April 2006 following comments he made on the role of the Prime Minister in the selection of Church of England bishops to say that the terms of the Act of Settlement were anachronistic and that it was an outstanding example of bigotry and sectarianism in the United Kingdom . . . but did not receive a reply.”

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