NRL head of football Todd Greenberg said the video referees would operate from a central command centre with access to every available camera angle, but the current video refereeing system would remain in use for the selected games and to provide a genuine comparison.

Greenberg said it was hoped that the bunker system would provide greater accuracy and consistency by video referees in quicker time.

"A video referee sits in a box with one screen and he only sees what the producer from the broadcast gives him," Greenberg said. "Sitting in a central command area you would have a screen for every camera at every opportunity in the game in real time.

"That's a fundamental difference to how you make decisions, so we have got to work our way through it to see if it is plausible.

"We would measure the difference in decisions on how long it takes and get feedback from the people involved in making those decisions on what it was like seeing every camera angle in real time."

The bunker system was secretly trialled at several matches last season at Allianz Stadium but the central command centre was located inside the ground.

Greenberg said the next step was to trial it off-site.

"We are hoping by the midway point this year we will have some sort of recommendation of whether it is plausible or not, both with the technology and also the expense," he said.

Video referees have been in the spotlight this season, with NRL referees boss Tony Archer having to admit that Melbourne were denied a fair try in their 24-22 round two loss to Manly, while also conceding a try to Newcastle centre Dane Gagai in last Sunday night's 20-18 win over Gold Coast should have been overturned.

There was criticism of the decision to deny a spectacular try to Penrith winger Dallin Watene-Zelezniak in Monday night's 20-12 loss to Sydney Roosters at Allianz Stadium but Fairfax Media understands that Archer is backing the match officials involved.

"I think what this would do is highlight a couple of areas we focus on with video referees," Greenberg said. "One is consistency in decision making and clearly if you have less people making decisions on key moments in games you are going to get more consistency, and it is always about accuracy.

"Everyone expects that we get every decision right and clearly we are trying to, but if you put accuracy with consistency and you overlay that with making sure it is done in real time and we don't hold up the game, you can understand why it is problematic sometimes. So it is a difficult part of the game but a really important one that we are putting a lot of resources and energy into."