You're right, its a dumb use of the trust system, and frankly (according to me, anyway) pooya87 shouldn't even be on DT at all. I don't know how you could "silence the truth" as you don't have any kind of moderation power on this forum.

However, your trust against pooya87 is equally dumb and you should remove it. Doing some kind of tit-for-tat retaliation doesn't help your case. It just looks petty. I dunno if pooya87 even cares about being DT or not but if they do they won't leave politically-motivated trust ratings in the future.