The Montana State Prison’s spokeswoman public/victim information officer sent out an email Friday to newsrooms across the state (emphasis theirs):
Thank you for your recent articles and coverage of Montana State Prison. We appreciate your interest in the shortage of correctional officers.
I do have one request. Over the years, the professionalism of correctional staff has changed substantially. Whereas the term “guard†was appropriate historically, over the past decade, the training and expectations of prison staff have increased. We now use the title “correctional officer†to refer to the security staff in Montana’s prisons.  In keeping with that, it would help us if you would refer to prison staff as correctional officers and, where space is limited, as officers.
As one wiseacre in the newsroom noted, I suppose this means calling them “screws” is out?
For the most part, news reporting uses common words. I can’t say it happens with 100 percent certainty and reliability, but so long as the majority of people call them prison guards, newspapers will continue to call them that too.