The courts have looked at this both in Deleware, Vermont and Ohio.
The case in Vermont was the Berry case and the court did not answer it because they didn't need too. But the court did raise it. The court asked if a client comes into a lawyers office and speaks with a lawyer if that lawyer then talks to people in his firm including other lawyers and paralegals does that mean that the client can't expect privilege. The court seemed to indicate that it did not think so.
In Ohio, it is the McFarland case where someone wrote letters to the service department. The Plaintiff's attorney claimed that because the letter may have been read by a number of different people that there is no privilege. The court ruled that regardless of how many people read it or know it it is what is the expectation of the person who started the communication. The court ruled that the letters that dealt with purely spiritual matters were a privilege, those that didn't speak of purely spiritual nature were not.
In the Deleware case where the court found that there was no privilege. The court ruled in that manner not because multiple elders knew about it, which they did say would not have been a violation or a removal of the privilege. The court ruled that there was no privilege because the elders were the ones that initiated the conversation and that the teenage boy did not go to them. They also said that it was because the boy was punished by the reproof.