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ROME – As the dust began to settle last year on the Vatican’s troubled $400 million dollar land deal in London, and as the colossal dimensions of the failure it represents became clear, Pope Francis was determined to put someone on trial, including his former chief of staff, Italian Cardinal Becciu, along with nine other defendants.

Yet, under the heading of “be careful what you wish for,” Francis could find that the primary person on trial ends up being not Becciu and the rest, but himself.

That, at least, seems to be the new tactic defense lawyers rolled out Friday, when a Vatican tribunal led by veteran Italian jurist Giuseppe Pignatone conducted its latest hearing in a process that’s been underway for seven months and still hasn’t gotten anywhere close to considering the actual charges.

Instead, the process has been bogged down with preliminary procedural issues. Initially, they had to do with the prosecution’s alleged failures to turn over key evidence, including video tapes of interrogations of star witness Italian Monsignor Alberto Perlasca, objections that still haven’t been fully resolved.

On Friday, a new front opened in the struggles over whether this trial should ever get off the ground, this time focusing on the role of Pope Francis himself.

Specifically, defense lawyers Marco Franco, representing financier Gianluigi Torzi who helped broker the London deal, and Luigi Panella, representing the Secretariat of State’s former money manager Enrico Crasso, raised the issue of four legal decrees Francis issued at the start of the process, known as rescriptum. That, attorneys argued, violated due process, the Vatican’s own legal norms, and basic principles of human rights.

Panella charged that the rescripts undercut the legitimacy of the entire process, putting it “outside the laws of this state, but also outside the principles of a fair trial guaranteed by international human rights conventions and the Italian Constitution.”

In essence, the rescripts designate this investigation and trial as a “summary rite,” basically meaning that it’s been conducted on the basis of ad hoc measures that depart in some significant ways from the Vatican’s usual criminal procedure. Among other things, those measures authorized wiretaps and other means of electronic surveillance essentially at will, without the need for judicial review, and also allowed defendants to be detained without getting a judge’s approval.

In addition to doubts about whether such measures impugn the integrity of the process, there are also questions about conflict of interest. In theory, Pope Francis is the victim of the alleged crimes, which involve bilking the Vatican of millions in inflated fees, but he’s also the Vatican’s supreme authority and his rescripts clearly benefited the prosecution.

In most legal systems, the idea of independent judicial review is to level the playing field between prosecution and defense, and to ensure that someone with a vested interest in the outcome isn’t calling the shots. In this case, defense lawyers are arguing, the deck was stacked from the beginning.

Another reminder of the wide latitude prosecutors enjoy came earlier in the week, when Italian finance authorities carried out several raids in Rome and on the island of Sardinia targeted at individuals connected with Becciu. Talking with reporters during a break in Friday’s hearing, Becciu described the raids as a “blitz that distressed me so much.”

He said Italian financial authorities told him their hands were tied because the request for the raids came from the Vatican and, under Italy’s concordat with the Vatican, they were obliged to honor it.

Apparently, the raids were focused on charges that beyond the London scandal, Becciu also embezzled around $116,000 from the Secretariat of State’s funds and directed them to a Catholic charity in Ozieri in Sardinia run by his brother.

Bishop Corrado Melis of Ozieri called the raids “incomprehensible, insisting that an investigation last July turned up no evidence of wrongdoing, and voiced frustration that he has to defend himself and the diocese for the “umpteenth” time. Becciu insisted the continuing investigations are “a humiliation for the diocese and for the bishop” – not to mention, of course, for himself.

Whatever one makes of the situation, the fact remains that the raids occurred without judicial approval and there’s no Vatican court to which either Melis or Becciu can appeal for relief.

The next hearing in the trial is set for Feb. 28, and Pignatone is expected to rule on the defense objections on March 1. He also said Friday that at the March 1 hearing he’ll provide a schedule for future hearings and court activity – adding, ominously, “if there will be future activity,” in what some observers took as a sign that he’s considering tossing out the entire process.

Here’s the thing.

From the beginning of his papacy, Francis has not been bashful about exercising the powers of his office. Earlier in the week, we saw him issue two more motu proprio, meaning changes to church law on his own initiative, extending his already significant lead in the all-time issuance of the papal equivalent of Executive Orders. Supporters see the pope’s willingness to rule by decree as the resolve needed to make reform stick, while critics see it as arbitrary and excessive.

Up to this point, no one in the Vatican system was really in a position to assess authoritatively whether Francis ever abused his authority. Now, in a sense, that’s precisely the call Pignatone is being asked to make. While a Vatican tribunal can’t simply overturn a papal decree, since the pope’s personal authority is not a matter for judicial review, it could hold that this specific use of authority invalidates the trial, which would still be a major setback.

However things shake out, this latest turn in the Vatican’s trial of the century is a terrific lesson in the Law of Unintended Consequences. Pope Francis wanted this trial because he thought it was important to hold someone accountable – without anticipating, of course, that “someone” could turn out to be him.

Follow John Allen on Twitter: @JohnLAllenJr