Liverpool crashed out of the FA Cup on Saturday at home to West Brom in a game held up for nearly four minutes while referee Craig Pawson decided whether to award a penalty to the home side.
The Baggies also had a goal ruled out for offside using the system in their 3-2 win.
But Klopp believes Baggies defender Ahmed Hegazi escaped when he should have been sent off for a nasty lunge on Roberto Firmino.
Klopp said: “Harsh challenges should be picked up.
“If the video assistant referee is not responsible for something like that we should think over the rules again because the ref needs help in a situation like this.
“I’m sure he would have whistled if he saw it, would’ve seen it exactly how it was, but he didn’t. If you see it on television it’s just horrible.”