Is the Pope a Catholic? The gerontocracy that is the College of Cardinals is highly unlikely over the next two weeks to come up with a successor to Benedict XVI who will be anything other than a guardian of Catholic orthodoxy. Yet the coming conclave to elect a new pope may be tumultuous.

The old men who make the decisions only get to be cardinals in the first place through long compliance to canonical Catholic doctrine. Dissidents and mavericks rarely get red hats. So do not expect a Pope who will overturn church opposition to gay marriage, assisted suicide, abortion or even contraception, which Catholicism sees as all inextricably interwoven into its theology of life and sexual anthropology.

Change is a relative concept in a church where German bishops were regarded as very bold last week for suggesting that while, of course, women could not be made priests, they might now be made deacons. What further inhibits change is that all the voting cardinals were appointed by Benedict XVI and John Paul II, who promoted only men cast in their own conservative image. Even a figure as creatively orthodox as the Archbishop of Westminster, Vincent Nichols, has been denied a red hat.

That is not all. For the first time since the medieval era the outgoing pope has not died in office, so the time for choosing a successor has been truncated. Cardinals from across the globe rarely meet; many hardly know one another, have poor Italian and little sense of whom to vote for. Traditionally, the electors size one another up during preparations for the papal funeral and days of pre-conclave meetings, with their numerous receptions and dinners.

But this time there is no period of mourning. That will heighten the inbuilt tendency for cardinals to choose someone they already know. For all the talk about it being time for a pope from Africa, Asia or Latin America – people said the same thing last time – the chances are it will someone who is already a big beast in the Vatican jungle.

That was how Joseph Ratzinger got the job last time. After two decades as Vatican doctrinal watchdog, all the cardinals had met him. As Dean of the College of Cardinals he also delivered the sermon at John Paul II's obsequies.

This time, the Dean is ineligible. Cardinal Angelo Sodano is, at 85, too old to vote. He will see his task as blocking the man who succeeded him as Secretary of State (the Vatican prime minister), Cardinal Tarcisio Bertone, who has mismanaged the papal civil service to such a degree that left and right inside the church are united in declaring it to be corrupt and dysfunctional. For all his gifts as a thinker and teacher, Benedict was no governor.

Bertone is the camerlengo, the cardinal who runs the Vatican between popes. Both men will have key speaking roles in the pre-conclave meetings. Both are tainted characters. Though Sodano was a better curial administrator, he supported a prominent clerical sex-abuser, Marcial Maciel, whom Benedict XVI disgraced as soon as he became Pope. Insiders are preparing for a factious, and perhaps fractious, conclave in which there are no candidates head-and-shoulders above the others and there are at least 10 men in with a chance.

There is another problem. The cardinals must choose someone who can cope with the fact that his predecessor will be living in an old pope's home, within stone-throwing distance of St Peter's. Benedict has pledged his "unconditional reverence and obedience" to his successor. But he also said, "There is no returning to private life... I no longer wield the power of the office for the government of the Church, but in the service of prayer I remain, so to speak, within St Peter's bounds."

That may sound ambiguous but Benedict's secretary, Archbishop Georg Ganswein – known as Gorgeous George by Vatican-watchers – will remain as Prefect of the Papal Household and yet will reportedly be going to live with Benedict in a Vatican convent. Each morning he will go to work with the new pope and return home to the old one each evening. One Man, Two Guvnors may have nothing on that. The medieval spectre of pope and anti-pope looms in Rome where clerical memories are long.

Benedict's unseen presence may also put psychological pressure on the electors in the first stage of choosing a new pope, which is analysing the achievements and failures of the last one. Many of the latter are contained in a secret dossier Benedict commissioned after the "Vatileaks" prosecution of the papal butler who leaked secret documents to journalists. When Benedict read its exposure of Vatican intrigue and infighting, the Italian press reports, after years of coping with paedophile priests and episcopal cover-up, he decided that he did not have the strength to carry on. He locked it in his safe with the instruction that it should only be read by the next Pope. Whoever is elected should not expect an easy time.