I agree there can be unconscious bias, but with 30-odd umpires I just think that the range of conflicting biases, it probably wouldn't explain any discrepancy. But yes, certainly with some umpires it could have an effect.
But take Ray Chamberlain. To me, he strikes me as an umpire that is so determined not to be influenced by the crowd, he actually seems to favour the away team. I'd much rather have him for an away game than a home game.
Or Dalgleish. It really does seem that he loves giving the Eagles free kicks.
Or that Foot muppet, who just loves paying everything he sees.
There are umpires of a range of ability, quirks and biases. But with three umpires on the ground, and 30-odd in total, I just think it mostly washes out.
Also, I know I see more free kicks to Freo than are there, because I'm a Freo fan and that's how it works.
As a team, if one decision each game goes the other way, we would have won 50% of the free kicks paid.
As a group, the umpires would come together and examine the game. Someone from Freo would be on the phone some weeks. It seems more likely to me that Freo fans are more biased towards Freo than the umpires are against. But that's just me.
