Scarlets boss Simon Easterby wants "clarity" over television match officials' roles if foul play prevents a try being scored.
The issue has been debated since the Ospreys beat the Scarlets on Friday.
"There needs to be a bit more clarity on what the referee can ask the TMO [and] what the TMO can actually contribute as well," said Easterby.
At Parc-y-Scarlets on Friday, Welsh referee Leighton Hodges asked TMO Derek Bevan: "Try, yes or no?"
Bevan responded: "He [Fenby] lost it forward, scrum five, defending ball."
Scrum V pundits Stuart Davies, Robert Jones and Kingsley Jones agreed that Bevan could - and should - have directed Hodges to award a penalty try.
Scarlets head coach Easterby, the former Ireland flanker, says the issue is unclear but he also accepts that any change to the policy would need the approval of the Pro12's organisers from Wales, Scotland, Ireland and Italy.
England's Aviva Premiership TMOs have a wider scope to rule on crucial moments in the Premiership.
Easterby is unsure whether the Pro12 needs to follow that example.
But he believes what happened at Parc-y-Scarlets on Friday needs to be reviewed and hopes to discuss it with Welsh Rugby Union official Nigel Whitehouse.
"It's obviously a high shot, but I don't think George Stowers was looking to knock his head off," Easterby said of the incident against the Ospreys.
"I just think he was looking to stop Andy scoring a try.
"Now in the heat of the battle, whether you swing and hit the ball or the head, you're looking to prevent a try.
"I think if Andy hadn't been hit in the face, he would have put the ball down and scored.
"We've lost out in that incident. We can't do anything about that, but what we can do is prevent that from happening again whether it's for us or other teams.
"I'm not sure what he can and can't say and that's probably the reason for this conversation because there's no clarity there."