Umpire Rudi Koertzen insisted batting conditions had become "unfair" after England were twice allowed to go off for bad light in the fifth Ashes Test.
Koertzen and Billy Bowden take a light-meter reading
The gloom refused to lift on the fourth afternoon, preventing Australia from using their seam bowlers.
But even though two spin bowlers were operating the officials decided to offer the light to England's batsmen.
"As a batsman, you can lose the ball through the air when it's bowled slowly in bad light," said Koertzen.
England had no complaints after beginning their second innings with a slender six-run lead.
RULE ON BAD LIGHT
Law 3.9 (b) Suspension of play for adverse conditions of ground, weather or light
If at any time the umpires together agree that the condition of the ground, weather or light is not suitable for play, they shall inform the captains and, unless
(i) in unsuitable ground or weather conditions both captains agree to continue
or (ii) in unsuitable light the batting side wishes to continue, they shall suspend play
They lead 2-1 in the series and only need a draw to secure the Ashes for the first time since 1987.
Australia opted to go off for bad light during their innings on the second and third days - costing them at least an hour's batting on the first occasion, but only five overs on Saturday.
"We have tried to be consistent," Koertzen told Channel 4.
"With the fast bowlers there is an acceptable level and as soon as it dips below that level, you offer the light to the batsmen.
"In this case, with the spin bowlers on, we give them a bit more leeway but once we think it's unfair, that's when we offer the light."
The decision received the support of former Australia wicket-keeper and England selector Rod Marsh.
"You can't play Test cricket in this light; I don't care what anyone says," Marsh told BBC Test Match Special.
"It's unfair to the batsmen even if the spinners are bowling."