ROME – Classic slasher movies are notorious for the plot twist in which the villain, believed to be dead, pops back up for one last stab of the knife or lunge of the chainsaw. The take-away is that just when you think the scary part is over, get ready for another jolt.

It’s a lesson which, in a different guise, chief Vatican prosecutor Alessandro Diddi is learning the hard way right now.

Last December, Diddi, the Vatican’s Promoter of Justice, finally won convictions in the celebrated “trial of the century,” a multi-headed hydra of a case that required a whopping two and half years – not to mention 69 witnesses, 85 court hearings, and millions of pages of files and documents – to end in guilty verdicts against Italian Cardinal Angelo Becciu and eight other defendants for various alleged financial crimes.

Granted, the verdicts remain on appeal, and granted, Diddi has faced stiff criticism for his conduct of the trial. Yet no matter how nominal it may have been, it was still a win, and anyway, the ordeal at least seemed over.

Now, however, the question is whether the best qualifier for the apparent win isn’t so much “nominal” as “Pyrrhic.” At least four additional verdicts, some real and some metaphorical, are currently pending on the London case, which, collectively, could still snatch defeat from the jaws of victory.

First up is a civil case currently being heard before London’s High Court of Justice, brought by Italian financier Raffaele Mincione, one of the defendants convicted in the Vatican trial. It was Mincione who initially advised the Vatican’s Secretariat of State on the $400 million purchase of a former Harrod’s warehouse in the upscale London neighborhood of Chelsea slated for conversion into luxury apartments.

Mincione wants the London court to declare he acted in good faith in the transaction, which ended with the Secretariat of State selling the property at a loss estimated at roughly $140 million. If Mincione prevails, he could also request financial compensation for reputational damage.

The case has already proved embarrassing for the Vatican, as last November the High Court ordered it to turn over confidential messages between Italian Cardinal Pietro Parolin, the Secretary of State, and Venezuelan Archbishop Edgar Peña Parra, Parolin’s top deputy as the sostituto, or “substitute,”  despite claims from attorneys representing the Holy See that such disclosures would represent a “grave sin.”

This week, Peña Parra was in London to testify in the case and faced a grilling from British lawyer Charles Samek, representing Mincione. He’s slated to wrap up his testimony on Monday. So far, the questions have focused largely on Peña Parra’s interactions with another Italian businessman, Gianluigi Torzi, who took Mincione’s place in the London deal around the time Peña Parra replaced then-Archbishop Angelo Becciu, also convicted in the London trial, as the sostituto.

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It should be recalled that British courts in the past haven’t exactly been friendly to the Vatican with regard to the London affair.

In March 2021, Judge Tony Baumgartner of Southwark Crown Court reversed an order for seizure of assets belong to Torzi, concluding that the Vatican’s filings were full of “non-disclosures and misrepresentations” which Baumgartner called “appalling,” and finding that the Vatican had failed to demonstrate a reasonable basis to believe Torzi was guilty of criminal conduct.

While Diddi awaits the outcome of the London case, he’s also facing a challenge on another front, this one more intellectual and academic, though it could also have real-world consequences.

Since the Vatican trial began in 2021, a number of jurists and legal scholars have challenged its legitimacy, including the claim that basic due process protections were violated. Among other things, they’ve contended that four famous “rescripts,” meaning decrees, from Pope Francis at the beginning of the process stacked the deck in favor of the prosecution.

Such criticism has been sufficiently persistent that Diddi recently felt compelled to mount a lengthy defense in the pages of the Annali di Diritto Vaticano, or “Annals of Vatican Law.” His arguments brought a stinging rebuke this week from Geraldina Boni, an expert on both canon and civil law at the University of Bologna, as well as a consultant to the Pontifical Council for Legislative Texts and the president of an Italian government commission on religious freedom and agreements with religious groups.

In an interview on Thursday with the Roman newspaper Il Messaggero, Boni skewered Diddi’s argument that the rescripts didn’t impugn the integrity of the trial, since they only concerned the preliminary investigation.

“An investigation and a trial are intimately connected, and, in any event, activities carried out during the investigation also can’t violate the fundamental guarantees of the persons involved,” she said, arguing that this principle is grounded in both natural and canon law.

Boni warned that unless the defects in the Vatican’s system of criminal justice are remedied, the risk is that its verdicts won’t be recognized by the Italian state, and that it could also face sanction by the European Court of Human Rights.

The third verdict potentially facing Diddi is that of a review of the convictions in the “trial of the century” currently before the Vatican’s Court of Appeals.

Not only have the defendants challenged their convictions, but even Diddi himself has appealed the ruling, arguing that the court did not sufficiently endorse his claims that the defendants acted in a coordinated and knowing fashion to pull off their fraud. (The judges presented a summary of their conclusions in December, although the full version of their verdict isn’t expected to be completed before the fall.)

In this case, the risk for Diddi isn’t so much that the convictions will be overturned, though Becciu continues to voice hope in such a result, most recently in an interview in May with the German newspaper Die Zeit. In reality, it’s rare for the Vatican appeals court to set aside a tribunal’s findings under any circumstances, let alone such a high-profile case.

However, Diddi may end up regretting having demanded an evaluation of his legal theory, which could end up with a rebuke for prosecutorial overreach, even if the sentences themselves remain intact.

Finally, there’s also the curious matter of Libero Milone, the Vatican’s former auditor general, who’s seeking almost $10 million in damages for what he describes as his forced resignation in 2017 under pressure from Becciu and the then-head of the Vatican gendarmes, Italian layman Domenico Giani.

Milone lost an initial case before a Vatican tribunal in January, and last Thursday the Vatican appeals court held a brief hearing to consider whether to take up his appeal. If the judges decline to proceed, Milone would have the option of appealing to the Corte di Cassazione, effectively the Vatican’s supreme court, which is composed of a panel of cardinals currently led by American Cardinal Kevin Farrell.

(Milone’s former deputy, Ferruccio Panicco, originally was part of the appeal, but he died last June of cancer.)

Diddi opposed Milone’s claim when it was initially filed, arguing that it should be barred by the statute of limitations, and he’s also threatened to pursue charges against Milone for allegedly spying on other Vatican personnel during his tenure as auditor general. (Milone claims he simply hired an Italian investigation firm, Falco, to help his office review public records in Italy related to Vatican contracts and hiring practices, and that it had nothing to do with illegal surveillance.)

Although Milone may be unlikely to get any satisfaction from Vatican courts, Diddi’s involvement in the case may open yet another front in which both Diddi’s motives and tactics come into question.

To be fair, Diddi, a veteran Roman lawyer, should have known this job was dangerous when he took it. Still, it’s likely that even he would not have imagined that he could prevail in the biggest criminal trial the Vatican’s ever staged, and yet, somehow, run the risk of winning the battle but losing the war.