Those are good questions. There are communities that were founded as clerical institutes, that is, communities of priests. The Franciscans who run EWTN are one of them. Their legal name is Missionaries of the Eternal Word. They are Franciscan because they follow the Rule of St. Francis. However, they are not one of the orders that St. Francis founded. They are an independent public association of priests in their diocese. They are religious and they are priests. But they are founded to be an order of priests. Therefore, they follow the local custom. That is, to call a priest Father.
The Congregation of the Franciscans of the Renewal (CFR) founded by Fr. Benedict is in a very different kind of situation. They are a community of brothers, but they were in New York, where the local custom is to call priests, Father.
There is something in religious life, which is not really a law, it’s more of a practice. You incorporate the customs of the local Church into new foundations. The orignal Franciscan foundation was founded in Italy in 1209. The customs were different then. Priests who joined communities of brothers were called Brother. In the 20th century in NYC, a new foundation would yield to the custom there.
This does not mean that the priests are not brothers. They are very much religious brothers. It simply means that the use of the title “Father” is accepted by the brothers, because it is the local custom and this community should reflect the local Church, since it is founded there. St. Francis would not want a community of his brothers to enter into a conflict with the local Church, especially with the local bisop.
In fact, St. Francis forbade the criticism of priests, bishops, popes and the Church. That is a big no no for Franciscans, even when the Church has been wrong, Franciscans have had to remain quiet. The Franciscans can only elect to act differently if they are asked to sin.
I hope all of this helps.
Fraternally,
Br. JR, OSF