The Post Office was within its rights to warn staff about discussing the closure of Douglas and Ramsey Post Office under the Official Secrets Act.
This morning in Tynwald, the acting Attorney General was asked about the issue by Onchan MHK Peter Karran.
John Quinn said post office staff are all bound by the Act, and could face prosecution if they give away business or security details.
Staff airing their views on plans to close two Crown offices and resulting job losses, have been warned by management not to discuss the matter on social media.
Mr Quinn said the organisation was within its rights to remind staff of their obligations: