City of Secrets: The truth behind the Murders at the Vatican By John Follain

I have never quite understood the need for the Vatican City State, which as anoraks will be able to tell you is, at 109 acres, the world's smallest sovereign country. The theory is that the leader of the world's one billion Catholics cannot live under the authority of any secular government. The Vatican has therefore been, since 1929, an internationally-recognised spirit zone in which the Pope can operate freely without fear of interference.

Other religious leaders, of course, appear to do perfectly well without such special treatment. Canterbury, for instance, is not about to become an independent republic with Rowan Williams as President. Moreover by being an earthly ruler as well as a religious one, the pontiff can get himself into some less than edifying messes. Such is the lot of all governments, but if you specifically create a state that is founded on higher religious principles, then people expect better standards of it than elsewhere. So the organisation of daily life in the Vatican City State, its dealings with other governments and its handling of its own citizens have to be whiter than white if it isn't to bring the whole Catholic Church into disrepute.

In City of Secrets, investigative reporter John Follain shows emphatically that this territorial minnow is nothing short of a disgrace, housing as it does a staggering amount of hypocrisy, conceit, secrecy and double-dealing, not to mention the seven deadly sins. Far from being the next best thing to heaven, at times Follain makes it sound like hell.

The murders on which he hooks this unappetising portrait are those in May 1998 of Colonel Alois Estermann, newly-appointed head of the colourfully-clad papal army, the Swiss Guards, his Venezuelan former model wife, Gladys Meza Romero, and a young guardsman, Cedric Tornay. The official line is that Tornay had an undetected tumour on his brain which caused him to act irrational-ly and so take his revenge for a small grudge against Estermann by killing him and his wife, before turning the gun on himself.

However, like every other secretive society before it, the Vatican has not been very successful in persuading the rest of the world that it is telling the truth about this extraordinary incident. Closed worlds give rise to a culture of rumour and Chinese whispers and so there has been talk of Estermann being a Stasi spy, of Tornay having an affair with Meza Romero, and of the commander and the guardsman being part of an underground gay sex ring operating in a country that officially describes homosexuality as "a strong tendency towards an intrinsic moral evil". The cover of City of Secrets rather cleverly captures the range of this controversy with a picture of a row of Swiss Guardsmen, their plumed, medieval helmets either hung in shame or dipped to allow a careful scrutiny of their own genitals.

The clear model for the book is A Thief in the Night, John Cornwell's masterful 1989 investigation into the death of Pope John Paul I after just 33 days in office. It too tackled another Vatican scandal, coming in the wake of David Yallop's bestseller In God's Name which alleged a complex plot by wicked cardinals to murder the Pope who threatened to expose their financial and sexual misbehaviour. Cornwell damned the conspiracy theory but in the process produced an unforgettable picture of the sordid goings-on at a place meant to be God's business address on earth.

Follain, who pays lavish tribute to Cornwell in the acknowledgements, tries to pull off the same trick. So he eschews the headline-making controversy and instead establishes the case for the deaths being what they were officially reported as, but he then crucifies the Vatican for its handling of both the investigation and its inhuman treatment of first young Tornay and then his grieving family. Along the way we meet some very unsavoury church officials indeed - cynical, power-hungry princes, puffed up with self-importance who never for one moment entertain a thought of God. They are happy to lie, cover-up and manipulate the ageing, infirm and often plain senile Pope John Paul II in order to protect their own backs.

Though it is not his aim, Follain makes a powerful case for two immediate reforms. The first is that, like every other organisation in the world, the Catholic Church should make its MD retire when he is no longer up to the job rather than force him to die in office. The last pope to hand over St Peter's keys this side of the grave was Celestius V at the end of the 13th century. What possible spiritual succour is there for Catholics in watching successive old men killed off by a post whose demands would make a 25-year-old blanche? The only beneficiaries, as John Follain makes plain, are the cardinals and monsignori who run the curia - or Vatican administration - who get to do whatever they like (and their appetites are seemingly inexhaustible) in the name of a pope who is drifting in and out of consciousness up in the papal apartments.

And the second is that an international community which has signed up to an obligation to uphold basic human rights should insist that everyday running of the Vatican City State be handed over to competent Italian authorities. The Pope and his inner circle could be given diplomatic immunity, to protect their freedoms, but reform is urgently needed to allow full and independent judicial enquiries into such incidents as the deaths of the Estermanns and Tornay. Try as she might, Tornay's mother has still not been given any documents relating to the death of her son. Anywhere else in Europe, she could appeal to her MP or the courts for help in righting this injustice, but the Vatican is the world's last absolute monarchy and the Pope has not so far heard - or been allowed by his courtiers to hear - her anguished pleas.

This book is the latest in a long line of powerful indictments of what goes on behind the Leonine Walls that encircle the Vatican. Follain may lack a little of Cornwell's finesse, but he has produced a case that any other global institution would feel duty bound publicly to address. As it is, as I'm sure he realises, the Vatican will simply sweep his efforts under an already lumpy carpet and presume on the faith of Catholics to keep people in the pews docile. But as the recent revelations about the activities of paedophile priests have been making all too plain, a new age of democracy and accountability is slowing taking hold of the Catholic Church. Follain's book significantly adds to the pressure to root out corruption and its ungodly perpetrators.