NPR:

Does the Vatican control its Catholic bishops?

The answer could determine whether the Vatican can be sued in U.S. courts and be forced to open up its secret archives.
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"The pope is not a five-star general ordering troops around," [Vatican lawyer Jeffrey] Lena says. "He is not Louis XIV telling his minions what to do. The 'military command center' or 'absolute authority' models of the church in which Rome dictates orders by royal fiat is just wrong."

Lena says it is the bishop who controls his diocese and is responsible to operate it within the framework of canon law.

Also, from the Irish Post,

Although Pope Benedict has not been accused of any crime, British lawyers are considering whether he should have immunity as a head of state and whether he could be prosecuted under the principle of universal jurisdiction for an alleged systematic cover-up of sexual abuses by priests.

Meanwhile the National Catholic Reporter continues its outstanding reporting, and it calls into question whether or not the Vatican has oversight over bishops:

Maciel [the late Fr. Marcial Maciel Degollado the charismatic Mexican who founded the Legion of Christ in 1941] built his base by cultivating wealthy patrons, particularly widows, starting in his native Mexico in the 1940s. Even as he was trailed by pedophilia accusations, Maciel attracted large numbers of seminarians in an era of dwindling vocations. In 1994 Pope John Paul II heralded him as "an efficacious guide to youth." John Paul continued praising Maciel after a 1997 Hartford Courant investigation by Gerald Renner and this writer exposed Maciel's drug habits and abuse of seminarians. In 1998, eight ex-Legionaries filed a canon law case to prosecute him in then-Cardinal Joseph Ratzinger's tribunal. For the next six years, Maciel had the staunch support of three pivotal figures: Sodano; Cardinal Eduardo Martínez Somalo, prefect of the Congregation for Institutes of Consecrated Life and Societies of Apostolic Life; and Msgr. Stanislaw Dziwisz, the Polish secretary of John Paul. During those years, Sodano pressured Ratzinger not to prosecute Maciel, as NCR previously reported. Ratzinger told a Mexican bishop that the Maciel case was a "delicate" matter and questioned whether it would be "prudent" to prosecute at that time.

In 2004, John Paul -- ignoring the canon law charges against Maciel -- honored him in a Vatican ceremony in which he entrusted the Legion with the administration of Jerusalem's Notre Dame Center, an education and conference facility. The following week, Ratzinger took it on himself to authorize an investigation of Maciel.

John Paul's support gave Maciel credibility as he moved with seamless ease among the ultra-wealthy.

Gordon Brown has one genuine chance left. He must employ the Vatican, as their public relations team operates at a level of utter genius. Somehow, while they're embroiled in an international paedophile scandal, they've fixed it so the person who's had to apologise is the Archbishop of an entirely different faith....

The Vatican has objected that the percentage of paedophiles in the priesthood is lower than in society as a whole. Who knows what polling company produced those figures but the problem isn't that some priests abuse children, it's that the ones who do it have been protected by their holy bosses.

It may be that a similar percentage of gas fitters are child abusers, but if they're caught they're sent to the police, and not told that as long as they quietly slip off to a different parish they can still advertise themselves as Corgi registered.
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And with your normal paedophile case, if someone suggests the institution that protected them will lose credibility as a result, the media reaction isn't "Hmm, well that seems a little strong."