From The BBC:

A senior Catholic scholar has defended the Vatican's decision to put Pope Pius XII, who led the Catholic Church from 1939 to 1958, on the road to sainthood. Pope Pius has long been accused by Jewish groups and scholars of turning a blind eye to the fate of the Jews.

A Vatican commission of cardinals and bishops unanimously voted this week for him to be considered for beatification. Professor Peter Gumpel said there was no truth in any of the allegations raised about the late Pope.

He said that, as far as he was concerned, the objections that had been raised over the years had now been researched and discounted.

"The case against Pius has been studied at length and in detail by many serious and independent scholars," said Professor Gumpel, a German Jesuit who contributed to the commission's work.

"I would not have signed the research papers that we put forward to the commission if I believed there was any truth behind the objections or allegations that were raised."

Full BBC Article Here

I am left to wonder why then did Pope Pius abstain from signing the Allied Declaration condemning the extermination of the Jews? Perhaps the Vatican's willingness to share information found in it's pre-war archives will explain this once, and for all.