Jon Rudd, coach of champion swimmers Ruta Meilutyte and Ben Proud, says sport governing bodies should lose the power to impose bans on drugs cheats.
Rudd believes the World Anti-Doping Agency or International Olympic Committee must impose bans.
"That way we're more likely to have a credible, transparent and fair results," he told BBC Sport.
"At the moment we get different results for different athletes from different countries for different sports."
Rudd, who is also head coach of the Plymouth Leander club, led the English team at the 2014 Commonwealth Games, where Proud won gold in the 50m freestyle and 50m butterfly events.
He has coached Lithuanian breaststroker Meilutyte, 19, since 2010, helping her become Olympic, World and European 100m breaststroke champion, as well as breaking the world record at both 50m and 100m.
One of Meilutyte's main rivals - Russian swimmer Yulia Efimova - has had her provisional ban for testing positive for meldonium lifted.
"WADA are there with it, they know what they want to do, but they're under-resourced," Rudd continued.
"The IOC want to get it right - it's the governing bodies of each of the individual sports that we need to stand behind.
"Sometimes they're compromised financially, with certain countries that are maybe helping to resource their sport that then pressurise them into making decisions that are maybe not what the WADA code tells us should be the decision.
"That's why we see different results for different countries. We get a particular drug taken by a particular athlete in a particular way, and this athlete in country X gets a four-year ban and this athlete in country Y, doing exactly the same thing, gets a tap on the wrist.
"That's the thing that's not right. We either have a zero-tolerance policy or we don't, and if we don't, then we need to stop saying we've got a zero-tolerance policy."
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