The Conjuring really captures the genre as the story is told by film companies. The only people available to confront manifest evil are in the employ of the Catholic Church, somehow. In this case, the film is sympathetic to the Catholic Church, and when the "Exorcism" is done, it is done in Latin. One could say it's a kind of Vatican II Exorcist, taking place in 1971, complete with cultural references made for comic relief. The hero, Ed Warren (Patrick Wilson), is supposed to be the only layman who is recognized as a demonologist by the Church, while his wife Loraine (Vera Farminga) is a powerful clairvoyant who seems to walk between worlds as she confronts the malevolent forces.
The film even has that retro technovision 70s feel, but it's surprising they couldn't quit capture the relentless ambiance of the time as the Exorcist did.
At the time of the film's setting, the Church was undergoing a kind of Revolution. There were Lay Extraordinary Eucharistic Ministers, Lay Lectors, Altar Girls and now, Lay Exorcists.
Here's how she responds to the question of her husband performing the "Exorcism" in an interview for Global Christian Post:
CP: During "The Conjuring" your husband Ed, played by Patrick Wilson in the film, performs an exorcism without the permission or assistance of the Catholic Church. What is your criterion when it comes to performing an exorcism? And was that a real event in your life?
Warren: In the Perron case, the family at that time did not have any religion. I don't know how it is now. There were six children and a mother. The father worked in New York and he came home usually on weekends. So [my husband] ... would command the demons in the name of Jesus Christ to go back to where they came from. He always did it in God's name.
In a surprising outburst of clericalism, Catholic News Service is very concerned about the credentials of the Ghost Buster couple, and quite rightly reasserts the need for the Rite of Exorcism to be conducted by clergy with the approval of the local ordinary.
One of the problematic issues from the standpoint of getting an exorcism is that none of the Perron children are baptized. It's actually a problem identified by Vera Farminga herself, but we also point out that the subject of the real life Exorcism dramatized by William Blatty in the celebrated film, The Exorcist, wasn't baptized either, but was invited to stay with the Vincentians of St. Louis while two priests took on the devil over a very long period indeed.
Although the article doesn't mention this, it's supposed to be very dangerous to confront such entities. Challenging the powers of darkness can bring disaster. The film is also not as explicit about the need for the Catholic Faith in confronting these beings. Not as explicit as Mrs. Farminga is.