Slaven Bilic feels Jon Moss was influenced by the Leicester City crowd after he gave a last-minute penalty to the hosts in Sunday's thrilling 2-2 draw.
Moss dismissed Leicester goalscorer Jamie Vardy for diving and awarded West Ham a penalty, converted by Andy Carroll, who was then adjudged to have fouled Jeffrey Schlupp in the box in the last minute of stoppage time.
Leonardo Ulloa scored from 12 yards to move the Premier League leaders eight points clear of second-placed Tottenham, who travel to Stoke City on Monday.
The Foxes fairytale title bid was far from Bilic's thoughts, however, as he reflected on two points dropped.
"We are gutted because I think we did enough to win the game," Bilic told Sky Sports.
"The last five seconds of the game, where we made one mistake, we didn't want to kick long balls and lost the ball there, then that move... the penalty.
"You want me to talk about the penalty? That's why you called me here... it was hard.
"The game went that way, it was hard for the referee, with the crowd, not only here, they're always asking.
"Every long ball is a handball or a penalty, so it's not easy for the referee. To be fair, I feel for him but it's not a penalty of course.
"You don't have to speak to Andy, it was not a penalty. The guy went down, he made a touch and went down, but I'm saying with all this pressure and situation, they are top of the table, and you have 30,000-whatever people screaming on every decision, it's hard for him."
Leicester felt aggrieved as Wes Morgan was penalised for tugging Winston Reid's shirt for the visitors' spot-kick.
While Bilic said he understood why the hosts were upset, it was not because he thought they were in the right.
He explained: "To be fair on one hand Leicester is right when they say 'why a penalty' because I think that's all year basically.
"Inside the box, outside the box, in set-pieces, in long throw-ins they play that kind of football and many times they get away with it."