Webster appeared to hack down Scunthorpe striker Akpo Sodje in the first half, but Byron Whitestone did not even book the big defender and Laws was sent ot the stands for his protests.
Webster, James Hayter's penalty and League One player of the month Paddy Madden racked up the Somerset side's eighth consecutive league win.
Laws said: "I was very disappointed with the referee's decision. It could have changed the whole complexity of the game.
"There is not an ounce of doubt about it and when you look at the DVD it is even clearer. That's the astonishing thing.
"The lad took Sodje out - he wouldn't be walking off with a twisted ankle if he just fell over. I think the referee lost the plot a little bit.
"It's a sending off, it doesn't matter which division you are in. When it's clear like that I've got every right to say something.
"I think it was a game too far for us. I'm relying on a small squad of players and when the same 11 have been at it for the last three games, it's a tough ask.
"I thought Yeovil were the better side, they took their chances and we didn't perform as well as we have done."