Further below, Joe Harrington comments that the opening of mail was a common practice at Flag in 1989/90. Actually, it is wider than that. Roger's remark reminded me that there is a Hubbard policy letter that ALL mail into the organization is to be opened and the reason he gives for this is to ensure that there are no bills coming into the organization that will be missed.
But what it allows (and did allow) was the monitoring of mail to staff. If a staff member is under suspicion and the RTC/OSA/Dept20 personnel want to monitor him/her by reading their mail, they simply ask HCO (where the mail comes in) to route that person's mail to them. They can read it, photocopy it for the Intell files and send it back to HCO so it can go on the person. If the person complains or asks why his/her mail is opened, the policy on opening mail to find bills is cited by HCO, which is a party to this. The role of Dept20 is kept out of it. Meanwhile Dept20 has the names of family, addresses, phone numbers, intimate information, all in the files that they can pass over to their agents/private investigators or use any time they want.
Incoming mail of staff was a key source of information for the Intelligence Bureau, using that policy as a ruse.
Two policies I could quickly find:
HCOPL 7 Oct 70 Mail Line "The mail opener opens all mail, whether personal or otherwise and no matter how marked on the cover..." HCOPL 31 Aug 65 Mail Opening "...done in Dept of Communications - HCO Division 1"Robert Vaughn Young