Who discerns apparitions and private revelations?
From the 1978 document(unofficial english translation) from the Congregation for the Doctrine of the Faith on discernment of apparitions.
What is Involved in Apparition Discernment?
The CDF released a document in 1978 which had been available only to bishops. In that document, criteria was laid out for the discernment of apparitions. It is a process for bishops to follow since they are the first level of ecclesiastical authority with jurisdiction. It has since found it's way into the public domain. Apparitions since 1978 fall under this, as well as those still under investigation prior to 1978.
Apparitions True and False
As a prelude, I should state my own interest in private revelations. I have visited Paray-le-Monial (where Jesus showed His Sacred Heart to St. Margaret Mary in the 17th century). I have visited Rue de Bac (where the Miraculous Medal was given to St. Catherine Laboure in 1830). I have visited Lourdes, Knock, and Fatima, and also the two Belgian towns where Our Lady appeared: Beauraing (1932-33) and Banneux (1933). I wear the Brown Scapular and the Miraculous Medal. I have conducted Holy Hours to celebrate the Feast of Divine Mercy since 1993.
I think, from all this, you can see that I am not opposed to private revelations. But I am opposed to false revelations; I am opposed to dubious revelations; I am opposed to disapproved revelations; I am opposed to obsession with private revelations. I am opposed to all these things precisely because I do believe in genuine private revelations and their role in the life of the Church.
The abundance of alleged messages and revelations in the past 40 years makes ever more necessary the traditional caution and discernment of spirits. Amid today's confusion and spiritual wasteland, many Catholics are seeking contact with the supernatural via new private revelations, regardless of whether or not they have been approved, or even whether or not they are in accordance with the Faith.
Canonical Sanctions against Fr. Tomislav Vlasic
As posted on the Diocese of Mostar-Duvno website:
The Canonical status of Rev. Father Tomislav Vlašić, OFM
The Bishop, 2008-08-31
The CONGREGATION FOR THE DOCTRINE OF THE FAITH with its letter prot. 144/1985-27164 of 30 May 2008, has authorized me as the local Bishop of the Diocese of Mostar-Duvno to inform the diocesan community of the canonical status of Fr. Tomislav Vlašić, the founder of the association “Kraljice mira potpuno Tvoji – po Mariji k Isusu” – (Queen of Peace, totally Yours – Through Mary to Jesus).