Was it suicide or murder? Was it really credible that an elegantly dressed businessman would stuff his pockets with banknotes and 11 1/2-pounds of bricks, and then string himself up from a precarious platform just above the Thames? On the other hand, was it really conceivable that professional killers would have gone to the trouble to do this to him?
At last, it seems something approaching an answer is at hand. This week Italian prosecutors issued arrest warrants for two key figures in the Calvi saga: his friend and confidant, the Sardinian businessman Flavio Carboni, and the notorious treasurer of Cosa Nostra, Pippo Calo.
The hypothesis, backed by 90 pages of closely argued deposition papers, is that Calvi was killed by the Mafia because he had either misused or embezzled millions of dollars of their assets. Since his fraudulent financial empire was on the brink of collapse, the prosecutors claim, he risked revealing the details of his Mafia links to the state authorities.
The indictments of Carboni and Calo are the result of five years of investigation based on the testimony of several senior members of the Mafia who have decided to collaborate.
The new evidence confirms many earlier suspicions about Calvi's murky links with the criminal underworld and the notorious P2 Masonic lodge, and casts new light on his extraordinary dealings with the cream of Italy's financial establishment, including the Vatican bank.
Calvi's descent into the shadows originated from his association with Michele Sindona, a Sicilian financier who enjoyed similar access to the Italian business and political elite and the Vatican, but in reality was a fraudster in cahoots with the Mafia. Sindona too died mysteriously, poisoned by a coffee laced with cyanide inside the maximum security prison where he was serving a life sentence for the murder of the magistrate who exposed his financial dealings.
Through the networks established by Sindona, Calvi began using his Banco Ambrosiano to circumvent Italy's strict laws on the export of foreign currency. Then, in the late 1970s, he acted as Cosa Nostra's chief money- launderer, siphoning off billions of dollars from the heroin trade into a network of front companies stretching from Europe to the Bahamas. His financial trickery included illegal transactions with the Institute for Religious Works, also known as the Vatican bank, as well as alleged dealings with Licio Gelli, the grandmaster of the P2 lodge, the secret network that penetrated deep into the Italian state and is suspected of attempting to subvert it.
Carboni was, according to the prosecutors, the man who introduced Calvi to Calo and other Mafia bosses and the man who, ultimately, betrayed him and set up the mechanism for his murder. A week before his death, with his creditors closing in on him and the Vatican urging repayment of at least pounds 154m that he did not have, Calvi undertook a frantic final journey across Europe. His itinerary was never clear, but appears to have included stops in Austria and Switzerland before his arrival in London.
He had asked Carboni to arrange a discreet bolthole for him in London and was horrified to find himself booked into the cavernous Chelsea Cloisters. According to the deposition papers, Carboni deliberately picked the Cloisters because of its size and because it had a back entrance enabling Mafia thugs to enter unnoticed.
Calvi was thus abducted and strangled somewhere between the hotel and Blackfriars Bridge with the same orange cord that was later found tied around his neck.
"Calvi was killed out of revenge," the Mafia super-informer Tommaso Buscetta has testified. "He was given Mafia money to recycle and he made poor use of it."
Why has it taken so long to reach this conclusion? Part of the reason is the British judicial system which, perhaps because of a lack of familiarity with the extraordinary workings of the Italian underworld, first ruled that Calvi had committed suicide and then, in a second hearing, returned an open verdict. It took a detective agency hired by the Calvi family and the revelations of the Mafia informers to unearth the full ramifications. "Had we known at the time what we now know, a completely different verdict would have been found," the foreman of the second jury, Bruce Kitchen, said as far back as the mid-1980s.
One remaining question is the identity of the killers. One name mentioned by some of the Mafia informers is Francesco Di Carlo, a Sicilian thug jailed in Britain in 1987 for drugs trafficking who has begun to talk extensively about the affair since being extradited to Italy last June. Di Carlo says he was approached to carry out the murder but was not available at the time. He has pointed the finger instead at Vincenzo Castillo, a member of the Neapolitan Camorra who was himself murdered shortly after the Calvi affair.