Or perhaps an admin didnt see it or there were no admins on?
You know we admins cant see the WHOLE battlefield and EVERY SINGLE ACTION. We react to anything we do see and catch. If an admin was on report it to him, even if you have to spam i chat. Most likely if an admin was on, since the admin did not see it he will watch, spectate or warn whoever you report.
As for claims of bias, between Rangerbob, Canary, and myself we have kicked/banned more Chaos for inappropriate action than the rest of the admins combined. If you see Chaos acting inappropriately please report it to an admin that is on or take screenshots and post in the ban/unban section.