TL;DR
Is it ever appropriate to raise with HR that a colleague has made (subsequently disproved) accusations against colleagues in past workplaces?
Background
A manager at my company (let's call him manager X) has been accused of a serious breach of workplace policy (bullying) by Employee A, who reports to Manager X. If proven, the accusation would likely result in immediate dismissal of Manager X and would permanently damage his career.
I am aware of the issue after a HR representative queried how my interactions with Manager X had gone. I don't report directly to Manager X but have occasionally worked on projects run by him. In my experience, Manager X is a regular mid-level manager and hasn't demonstrated any behaviours that resemble bullying. The HR representative noted that the issue was particularly difficult to resolve because the accused bullying only occurred when no one else was around.
By chance, Employee A and I worked at another company a few years ago, again in different teams. In that company Employee A made very similar accusation against two of his successive managers. In both instances formal investigations were completed which exonerated the accused managers. This was possible because of statements from colleagues who said that Employee A grossly exaggerated events and other events could not have taken place because people were in different cities at the time. Employee A left the previous company shortly after the second accusation was dismissed.
Question
Is it appropriate to mention to HR my knowledge that Employee A has a history of making similar accusations against their manager given:
- I've been asked by HR to comment on my experience in dealing with Manager X and nothing else.
- I have no evidence to disprove what Employee A is now claiming about Manager X.
- While I believe the investigations that took place at the previous company were thorough and unbiased, I have no evidence to confirm that.
- BUT in the absence of any third-party information (just what Manager X and Employee A say), I have no doubt that Manager X will be dismissed "just to be on the safe side", which information relating to Employee A's past behavior may prevent.