I've seen some really, really heinous attacks leveled against Lefties by Righties stay up for hours or even days, while even the gentlest of criticism of right-wing trolls gets posts banned. 

Hence the thought that right-wing bias may be happening. 

On the other hand, if you get your post removed, you might think your particular political ideology is biased against....so there IS some solace in the notion that both sides think they are being discriminated against.