If you truly value openness on your Agile teams, you must untangle them from the grapevine.
Openness is one of the core scrum values. As stated on Scrum.org:
“The scrum team and it’s stakeholders agree to be open about all the work and the challenges with performing the work.”
This is a very broad statement, encompassing not only openness around work products and processes, but also each individual’s responsibility for ensuring that any challenges related to overall team performance are identified, acknowledged, and resolved. In my experience, issues with openness related to work products or the processes that impact them are relatively straightforward to recognize and resolve. If a key tool, for example, is mis-configured or ill-suited to what the team needs to accomplish than the need to focus on issues with the tool should be obvious. If there is an information hoarder on the team preventing the free flow of information, this will reveal itself within a few sprints after a string of unknown dependencies or misaligned deliverables have had a negative impact on the team’s performance. Similarly, if a team member is struggling with a particular story card and for whatever reason lacks the initiative to ask for help, this will reveal itself in short order.
Satisfying the need for openness around individual and team performance, however, is a much more difficult behavior to measure. Everyone – and by “everyone” I mean everyone – is by nature very sensitive to being called out as having come up short in any way. Maybe it’s a surprise to them. Maybe it isn’t. But it’s always a hot button. As much as we’d like to avoiding treading across this terrain, it’s precisely this hypersensitivity that points to where we need to go to make the most effective changes that impact team performance.
At the top of my list of things to constantly scan for at the team level are the degrees of separation (space and time) between a problem and the people who are part of the problem. Variously referred to as “the grapevine”, back channeling, or triangulation, it can be one of the most corrosive behaviors to a team’s trust and their ability to collaborate effectively. From his research over the past 30 years, Joseph Grenny  has observed “that you can largely predict the health of an organization by measuring the average lag time between identifying and discussing problems.” I’ve found this to be true. Triangulation and back-channeling adds significantly to the lag time.
To illustrate the problem and a possible solution: I was a newly hired scrum master responsible for two teams, about 15 people in total. At the end of my first week I was approached by one of the other scrum masters in the company. “Greg,” they said in a whisper, “You’ve triggered someone’s PTSD by using a bad word.” 
Not an easy thing to learn, having been on the job for less than a week. Double so because I couldn’t for the life of me think of what I could have said that would have “triggered” a PTSD response. The only people I knew who had been diagnosed with PTSD were several Vietnam veterans and a cop – men who had been through violent and life-or-death circumstances. This set me back on my heels but I did manage to ask the scrum master to please ask this individual to reach out to me so I could speak with them one-to-one and apologize. At the very least, suggest they contact HR as a PTSD response triggered by a word is a sign that someone needs help beyond what any one of us can provide. My colleague’s responses was “I’ll pass that on to the person who told me about this.”
“Hold up a minute. Your knowledge of this issue is second hand?”, I asked.
Indeed it was. Someone told someone who told the scrum master who then told me. Knowing this, I retracted my request for the scrum master to pass along my request. The problem here was the grapevine and a different tack was needed. I coached the scrum master to 1) never bring something like this to me again, 2) inform the person who told you this tale that you will not be passing anything like this along to me in the future, and 3) to coach that person to do the same to the person who told them. The person for whom this was an issue should either come to me directly or to my manager. I then coached my manager and my product owners that if anyone were to approach them with a complaint like this to listen carefully, acknowledge that you heard them, and to also encourage them to speak directly with me.
This should be the strategy for anyone with complaints that do not rise to the level of needing HR intervention. The goal of this approach is to develop behaviors around personal complaints such that everyone on the team knows they have a third person to talk to and that the issue isn’t going to be resolved unless they talked directly to the person with whom they have an issue. It’s a good strategy for cutting the grapevines and short circuiting triangulation (or in my case the quadrangulation.) To seal the strategy, I gave a blanket apology to each of my teams the following Monday and let them know what I requested of my manager and product owners.
The objective was to establish a practice of resolving issues like this at the team level. It’s highly unlikely (and in my case 100% certain) that anyone new to a job would have prior knowledge of sensitive words and purposely use language that’s upsetting to their new co-workers. The presupposition of malice or an assumption that a new hire should know such things suggested a number of systemic issues with the teams, something later revealed to be accurate. It wouldn’t be a stretch to say that in this organization the grapevine supplanted instant messaging and email as the primary communication channel. With the cooperation of my manager and product owners, several sizable branches to the grapevine had been cut away. Indeed, there was a marked increase in the teams attention during daily scrums and the retrospectives became more animated and productive in the weeks that followed.
Each situation is unique, but the intervention pattern is more broadly applicable: Reduce the number of node hops and associated lag time between the people directly involved with any issues around openness. This in and of itself may not resolve the issues. It didn’t in the example described above. But it does significantly reduce the barriers to applying subsequent techniques for working through the issues to a successful resolution. Removing the grapevine changes the conversation.
References Grenny, J. (2016, August 19). How to Make Feedback Feel Normal. Harvard Business Review, Retrieved from https://hbr.org/2016/08/how-to-make-feedback-feel-normal  The “bad” word was “refinement.” The team had been using the word “grooming” to refer to backlog refinement and I had suggested we use the more generally accepted word. Apparently, a previous scrum master for the team had been, shall we say, overly zealous in pressing this same recommendation to a degree that it became a traumatic experience for someone on the one of the teams. I later learned this event was grossly exaggerated. The developer had a well known reputation for claiming psychological trauma to cower others into backing down and would laugh and brag about using this club. The strategy described in this article proved effective at preventing this type of behavior.