The boss feels the influence of Chelsea players and coaching staff may have had an effect of referee Phil Dowd's decision to brandish a second yellow card so soon into the game
The Spaniard was sent off in the first half of Sunday's 1-0 Premier League defeat at home to title-chasing Chelsea after receiving two yellow cards in quick succession, but Dowd took his time over producing the second for a foul on Andre Schurrle.
Monk believes that the experienced official could have shown some leniency, with the second infringement coming just two minutes after the first, and suggested that the vocal reaction of the visiting players and coaching staff may have had an influence.
"I guess if you go letter of the law, it is a sending off," he told reporters. "But I think if you go letter of the law in every single game, you'll have six or seven sending offs a game.
"The more disappointing thing is, he looked like he signalled straight away 'no', as if to signal it isn't warranting another yellow.
"For their bench and manager to then surround the fourth official, and their players to surround the referee himself, and then the red card come later on - it makes you wonder doesn't it?"
But Monk - backtracking somewhat - refused to question Dowd's integrity.
"I know Phil. He's always been honest with me and he's an honest guy, so I'm not doubting that at all," he continued. "If he says that it's him giving himself time then it's him giving himself time.
"If you go by letter of the law, it is a sending off, so what can I do? I can't really complain."
Monk stopped short of expressing disappointment in Chico, whose dismissal was followed by a second-half Demba Ba winner, but admitted that the Spanish centre-back could have dealt with his early booking better.
"He's an experienced pro and he should have used that experience in terms of that situation," he added.
"We've all - as players - been in that situation where you get booked, especially early on, and you're treading a tightrope for the rest of the game. But you have to manage it properly."