But Catholics locked Jews in walled ghettos for centuries, so it would be poetic justice to see Father Riccardo and Bill Donohue and Brian Brown locked up in a walled ghetto.
So this statement is a little problematic. The relationship between Christians and Jews in the Middle Ages is a rather complex one. But, in general, the expulsions and persecutions were not instigated by the Church hierarchy.
Expulsions of Jews were generally instigated by the secular authorities. For instance, in England, Jews were extended royal protection in exchange for heavy taxation. They were able to pay that heavy taxation because they had a monopoly on lending money at interest (typically around 40-50% per year) due to a prohibition on usury by the Catholic Church. And the people who owed money to the moneylenders tended to be the landed aristocracy. A couple of the clauses in Magna Carta specifically try to regulate debts owed to Jews. Once the Jewish community became less useful to the Crown (often because others found ways around the usury prohibition), it became politically expedient to expel Jews (who were mistrusted by the commoners for superstitious reasons and hated by the nobility for economic reasons), which Edward I did in 1290 (they were not legally permitted to return until 1657).
On the other hand, outright mob violence against Jews generally arose from the blood libels (accusations of murder of Christian children for ritual reasons, desecration of the Host, etc.) which periodically arose and spread among commoners, and generally represent the typical superstition and fear of "the other" that is a common feature of human nature, compounded by anti-Pharisaical passages that appear throughout the New Testament. These were usually fairly localized events, but a particularly grisly episode happened as part of the First Crusade in 1095-6, when Jewish communities in several German cities were massacred.
But it should be noted that the Church hierarchy generally sought to protect the Jewish communities that it could. The archbishops of Cologne and Speyer in Germany did their best to protect the Jews in their cities. The first walled ghettos went up there not to imprison Jews but to protect them. And Jews themselves generally embraced the ghetto because typically, within its walls, they were given wide latitude to govern themselves. Not to mention that if there had been extensive commingling between Christians and Jews, it's very likely Judaism itself would have been assimilated out of existence; Jews policed the boundaries between the two communities just as assiduously (if not more so) than Christians did. And still, in some cases
It's also true that the Catholic clergy bent over backwards during the Second Crusade to ensure that a similar attack did not happen again. For instance, Bernard of Clairvaux, the founder of the Cistercians, preached extensively in Germany to prevent a repeat.
That's not to say there weren't problems as well. The Fourth Lateran Council in 1215 asked secular authorities to force Jews (and Muslims) to wear special clothing distinguishing them from Christians (the forerunners of the patches that Jews had to wear in Germany in the Nazi period). This was to prevent accidental commingling...another attempt to police boundaries between the two communities. And while forced conversion was explicitly prohibited, Christian authorities could bring a lot of pressure to bear. This often took the form of forced disputations, where Jews were obliged to defend their beliefs against Christians. But conversion was always available as an option for Jewish communities that would otherwise be expelled. It was this choice of "convert or leave" that led to the rather fascinating experience of crypto-Judaism, especially in Spain following the expulsion of 1492, and the subsequent reaction against that in the form of the Inquisition.
It's actually a rather interesting history, and not anywhere near as one sided as is commonly thought.