The facts are more or less like this, with changed names and some other details, to make identification more difficult:
I belong to one of the learned professions and am a bit of an activist there. This means I go to conferences, speak, write, have a blog etc, often touching controversial subjects in the profession on which there are some dividing lines, sometimes a lot of money and power involved, for the other side at least, whose views and actions I disagree with. I’m well known and recognized, if not exactly a popular person (as it’s all about the subjects, not about me as a person).
There’s Forum 1 and Forum 2, of which the admins aren’t on speaking terms due to an old conflict that’s a distant memory now. The membership largely overlap, i.e. many professionals belong to both of the groups. I’m friends with the admins of Forum 1 and their friends, and we agree on most things (not all by far). However, I had no beef with the admin of Forum 2, who always talked friendly to me, though we only spoke 2-3 times a year. That admin is friends with some people who support the other side.
One day I found myself banned from forum 2 and in receipt of very surprising private correspondence from the admin, unloading a lot of verbal abuse and revealing himself to have been a closet enemy for some time, saying he was glad to have a ‘good reason’ to ban me. Turns out that ‘good reason’ was joke that he approved of when made but later chose to interpret as a metaphor about himself as a tyrant on that forum. Something I didn’t mean to say because I totally didn’t even think it. I was extremely surprised he’d even make that sort of link.
With misgivings, because I knew what the Catechism says on detraction, I went to Forum 2 and wrote a post because I didn’t want to have to suffer it in silence.
I restricted it to just disclosing the bare facts that 1) I was banned by the admin of the other group, I didn’t simply stop participating or leave it of my own accord; 2) the stated reason was a joke the admin first approved of but later chose to interpret as a metaphor describing himself; 3) there was no thematic connection between the joke and his person (thus the interpretation was unwarranted); 4) I had a good opinion of him, I didn’t even actually think what he claimed my joke implied.
I omitted and totally kept secret the verbal abuse I experienced from him, as I didn’t think people had to know about it. I didn’t want that one bad act to be the lens through which people would see and judge him. I didn’t publicize any of the matter on my website or blog or anywhere else like that except for a narrow circle of people with whom I shared more information.
Did I have an obligation to protect that guy’s reputation by total silence on all details of this?
I suppose the audience — fellow professionals — had a right to know what was going on in a thing like this, but my motivation was that I didn’t want to keep the ban a secret just to protect the guy’s reputation.
Discussion ensued, where audience provided additional information and started connecting the dots. It turned out that it was a deliberate hoax and PR coup by him and his buddy (both of the guys eventually stopped barely short of openly confirming it). I disclosed more information, and in any case there were some unfavourable posts about those guys, including some discussion of the manipulative buddy’s black PR operations in general. I think the profession is better off knowing. However, I’m not sure what I did was right.