Reports broke in Australia's Sydney Morning Herald recently that both the Three Lions and the Baggy Greens are under investigation by the International Cricket Council after a number of dubious DRS decisions throughout the current Ashes series.
Onions, who has been recalled to play in the fourth Test of the series, has leapt to the defence of himself and his teammates.
"It was the the first I heard when I walked into the changing room today," Onions told Sky Sports News. "It seems completely blown out of proportion, it just doesn't seem right.
"I know that England players would never put anything on their bats. Tape has been used to mend cracks or people have favourite bats and use it to make them last as long as possible.
"It sounds completely silly to even think that people are putting things on their bats to try to help them to cover up decisions. From our point of view as players we don't put anything on our bats and we play the game as fair as we can, as I am sure the Australians do as well."
The fourth Test gets underway on Friday.