The following comes from a February 16 New Liturgical Movement article by David Clayton:

I just attended a talk by the exorcist for diocese of San Jose, Father Gary Thomas.

I wanted to pass on one little comment that he made almost in passing. I do not know where he stands liturgically in regard to the Mass – there was nothing in what he said that led me to believe that he celebrates the Latin Mass, for example. However, he did explain that the Rite of Exorcism is only said in Latin. One reason is practical – there is no approved translation in English as yet. He gave another reason why he was so strongly in favor of the use of Latin in the Rite of Exorcism: “The Devil hates Latin, it is the universal language of the Church.”

I asked him about this afterwards, and he repeated it, saying that his personal experiences as an exorcist who has performed many, many exorcisms have convinced him of this. He told me he had heard from exorcists who did exorcisms in Italian, Spanish and Portuguese (the only approved vernaculars for this Rite) that Latin was the most effective language.