Getty ImagesVATICAN CITY - NOVEMBER 24: Pope Benedict XVI sits in the Vatican, which can be sued for sexual assaults under a ruling Monday. (Photo by Stefano Dal Pozzolo-Vatican Pool/ Getty Images)The sexual-abuse litigation that has raged for years against the Catholic church just got a lot more interesting.

In a landmark ruling yesterday, the Sixth Circuit concluded that the Vatican could be held liable for negligence in sexual-abuse cases filed in the U.S. It is the first time a circuit court reached that conclusion,...