The resignation by Pope Benedict was merely expedient - he has become too old to cope. It would have been both astonishing and courageous, a few years ago, had it been offered in atonement for the atrocity to which he had for 30 years turned a blind eye - the rape, buggery and molestation of tens of thousands of small boys in priestly care.
His “command responsibility” for this crime against humanity goes back to 1981, when he was appointed Prefect (ie Head) of the Congregation for the Doctrine of the Faith, the Vatican body that disciplines errant priests. Although the CDF files are a closely guarded secret, letters from Cardinal Ratzinger have emerged in several US court cases, always protective of rapist priests. As father Hans Kung, the eminent Theologian, put it in his open letter to Catholic Bishops in 2010, “There is no denying the fact that the world-wide system of covering up cases of sexual crimes committed by clerics was engineered by the CDF under Cardinal Ratzinger”.
The worse case was that of Father Maciel, a bigamist, paedophile and drug-taker who raped his own children but had become a close friend of John Paul II. Ratzinger was in possession of all the evidence about Maciel but refused to act. Even after he became Pope, Ratzinger refused to defrock this monster priest or provide his affidavit to police. Instead he merely 'invited' Maciel to retire and lead a quiet life in the US, away from media attention. Ratzinger undoubtedly loathes such men, but he was always the ostrich Pope, the academic who kept his head in the sand until the storm hit.
Pope Benedict's Vatican has been an enemy of human rights. The fiction that this religious enclave is a “state” enables it to appear at UN conferences and to veto initiatives for family planning, contraception or any form of “gender equality”. Benedict himself has decried homosexuality as “evil”, and ruled that women have no right to choose, even to avoid pregnancies that result from rape or incest; IVF is wrong (because it begins with masturbation); condom use, even to avoid HIV Aids within marriage, must never be countenanced. There is no denying that his Vatican has been a force in international affairs, rallying the Catholic countries of Latin America to make common cause on moral issues with Islamist states like Libya and Iran.
As Head of a State - even such a make-believe state as the Vatican - Pope Benedict has absolute immunity from legal action. But this immunity is not the same after you retire. There are many victims of priests permitted by Cardinal Ratzinger to stay in holy orders after their propensity to molest was known, and they would like to sue the ex-pope for damages for negligence. If he steps outside the Vatican, a court may rule that they have a case.