The Pontifical Council for Legislative Texts on the 16th June 1998 issued a response to a dubium dealing with this issue. It was approved by the Pope on the 7th July 1998. The text can be found in (1) Acta Apostolicae Sedis Vol XC, 1998,p 711. The Dubium asked whether attending to can 964 par 2 of the Code of Canon Law, the minister of the sacrament, for a just cause and excluding a case of necessity, can legitimately decide,( legitime decernere valeat ) even if the penitent strongly demands otherwise ( etiamsi poenitens forte aliud postulet)that sacramental confession should take place ( excipiatur ) in a confessional ( sede confessionali ) with a fixed grill ( crate fixa instructa )
The response was affirmative.
Father George Donaldson
Lecturer Emeritus in Moral Theology
Scotland