Alan Watkins: The ravening beasts will not be satisfied by another portion of Mr John Prescott

His functions were to mollify the brothers and shield Mr Blair

The last deputy leader of the Labour Party to play croquet regularly or, for that matter, casually was Roy Jenkins. He took the game quite seriously; while Mr John Prescott, from what one can make out, was prepared to try anything once. It seems that croquet was the least of his misdemeanours, but England is a funny old country. For this harmless frolic Mr Tony Blair has deprived his Deputy Prime Minister, or perhaps the Deputy PM has deprived himself - for it is not entirely clear which it is - of his country retreat, Dorneywood.

My own view is that a Labour Government should have no business playing this degrading game of musical chairs or, rather, musical country houses for spare ministers. Mr Blair should be allowed to stay on if he made adequate use of the property, Chequers. But he seems to prefer to spend his spare time instead in Italy, Egypt, Barbados, or even further-flung corners of the globe.

For the moment Mr Prescott, as Mr Blair's Deputy, should have the run of Dorneywood, a pretty dismal sort of place, if you ask me. Mr Prescott is only the second Deputy PM under Labour to have held the post since Herbert Morrison in 1945-51. Under the Tories there was a long but irregular procession: Anthony Eden, R A Butler, William Whitelaw, Geoffrey Howe and Michael Heseltine.

Edward Heath refrained from appointing a deputy, as did Harold Wilson and James Callaghan likewise. Mr Blair's appointment of Mr Prescott in 1997 was accordingly as much of an innovation as it was a revival, for in Labour terms, the post had not existed for 46 years.

Mr Prescott's functions were to mollify the brothers from the branches, which tasks he shared with Mr Gordon Brown; to shield Mr Blair from hostile fire, as he continues to do, even if with lessening effect; and to keep out of mischief, though his luck is running out. Mr Prescott is wholly the beneficiary of Prime Ministerial patronage: the job could be withdrawn as easily as the free accommodation already has been.

Not so the deputy leadership. As the pamphleteer "Junius" put it to the Duke of Grafton in 1769: "The right of election is the very essence of the constitution. To violate that right, and much more to transfer it to any other set of men, is a step leading immediately to the dissolution of all government."

Since 1994 we have grown out of the habit of holding elections. Only in the Conservative and Liberal Democrat parties have the old traditions persisted. Like dancing round the maypole and crowning the Queen of the May. For the apparatchiks, there is always the opportunity for another fix.

In 1994 Mr Prescott won the deputy leadership fair and square. Mrs Margaret Beckett lost to both Mr Blair and Mr Prescott, but in 1992 she defeated Mr Prescott for the deputy leadership.

In 1968, George Brown resigned from the government but remained as deputy leader until 1970 when he did not stand and Jenkins succeeded Brown. It is an arguable point about whether Mr Prescott should be required to resign the deputy leadership under the new rules that were brought in 13 years ago. Brown, by the way, was never Deputy PM.

The new rules say that: "when the PLP is in government and the deputy leader [is] in Cabinet, an election shall proceed only if requested by a majority of party conference on a card vote."

The rules go on to say that: "when the party is in government and the deputy leader, for whatever reason, becomes permanently unavailable, the Cabinet may, in consultation with the NEC, appoint one of its members to serve as deputy leader until the next party conference. The Cabinet may alternatively, in consultation with the NEC, leave the post vacant until the next party conference."

Make of that what you will. The sole recent contested election in Government for deputy leader occurred in 1976, when Michael Foot defeated Shirley Williams. There have, by contrast, been abundant examples in opposition, of which the most narrowly and the most bitterly contested election was that of Denis Healey and Tony Benn in 1981.

Mr Alan Johnson tells us that he would be prepared to take up the burden if Mr Prescott were to lay it down. That, I suppose, is one way of looking at it.

Then there is what Victorian politicians used to called a "hum", meaning a popular buzz of speculation, in this case the call for a woman to become deputy leader. Ms Harriet Harman has gradually been working her passage back; while Ms Tessa Jowell has never entirely lost the good opinion of the Prime Minister, despite the distinctly odd company that she has been prone to keep over the years.

Quite why it is necessary to call for a woman deputy, when Mrs Beckett was a perfectly serviceable incumbent in 1992-94, is slightly mysterious. But there it is. The women's vote, both inside and outside the House, seems to have had something to do with Mr Prescott's present unstable position.

But there are even more powerful forces at work. In 1989, after Sir Anthony Meyer had unsuccessfully challenged Margaret Thatcher, that pantomime villain of the Whips office, Tristan Garel-Jones, warned his leader: "There are a hundred assassins lurking in the bushes, Prime Minister. Those people will come back and kill you."

It is not wholly fanciful to try out a dress rehearsal for the demise of Mr Blair. The new rules are in place. There are provisions for challenges for persons who become permanently unavailable (as the rules prettily call them), for card votes and decisions of the National Executive Committee and appeals to the annual conference.

Perhaps more likely is that Mr Prescott will go quietly, with a caretaker deputy leader or even a perfect and absolute blank; though Mr Johnson, for one, is fully prepared to come to the rescue should the summons arrive.

Mr Blair, Mr Prescott or both of them have contrived to fling a whole commodious residence to the ravening beasts of the Daily Mail. Mr Blair has thrown several chunks at them already. It may be that Mr Blair will have to sacrifice the whole of Mr Prescott to the forces of the women's vote and the Tory press. But no. The greater danger for the Prime Minister is surely for Mr Blair to sacrifice not only Mr Prescott but Mr Blair himself as well.