The Vatican is currently having a conference on satanism and exorcism.
They claim to be approaching the problem with "seriousness and scientific rigour" As if there were any scientific evidence of these phenomena. I find it difficult to believe that 21st century people can even talk like this. Do they have no insight into how stupid and archaic they appear? They obviously don't know what the word "science" means.
According to a Father Nanni you can recognise that someone is possessed because they “garble in foreign languages or nonsensical gibberish.” I don’t think he has to look too far.