I'm curious as to the actual grounds Dawkins and Hitchens are hoping to cite to 'arrest' the Pope. From the OP's article, I see a few powerful statements by the two New Atheists, and a reference to two high-profile lawyers who have apparently discussed the possibility of prosecuting (in a criminal or civil court) the Pontiff with the Crown Prosecution Service. Oh my! So what exactly are the specific allegations? What evidence is being presented? Regardless of one's one personal 'spiritual' beliefs, and opinions of the Catholic Church, everyone should be looking at this entire move with some extreme suspicion.
Regarding The California Priest Scandal, from what I've read of the situation, it's not at all as clear cut as the reports have suggested. For starters, the letter that was sent to the Vatican by the offending priest's bishop was about a request for laicization; it was not a letter detailing the priest's crimes. The letter was dated in 1985, and the delay the Pope allegedly recommended lasted until 1987, when the offending priest was officially defrocked (he had been removed from pastoral services long before the letter in question was even sent to the Vatican). Secondly, the local parish and public were already aware of the priest's trangressions: He had long been reported to the police and charged prior to this 1985 letter, thus making any suggestions the Pope conspired to cover up the situation utterly absurd. Thirdly, all evidence of the priest's trangressions was destroyed by the California civil courts system after he had completed his extremely light sentence - not by the Pope in his dark damp cell deep beneath St Peter's. Lastly, the office that the Pope ran in 1985, the Congregation of the Doctrine of the Faith, did not handle the pederast/pedophile priest cases until 2001 (the letter that the Pope received dealt solely with the laicization request, and nothing more). Why the press has failed to properly vet and present the story - in all the articles I've read in the papers, none have queried a canon lawyer about the contents of the letter and the canonical situation the abusive priest was in - is a question that ought to be at the forefront of people's minds.
Now I'm not saying the letter, and the delay in defrocking the priest, was the correct thing to do, but it is far from the type of clandestine conspiracy that some eager beavers have tried to make it to be.