DTM title contender Robert Wickens said BMW "used the politics of the series to their advantage" in the beginning of the season.
After the team claimed its car was not competitive enough, the BMW M4 DTM's base weight was reduced by 7.5 kg and its rear wing was widened by 5 cm at the beginning of the season.
Wickens, who is currently third in the standings as the top Mercedes driver, reckons allowing BMW to have both changes gave the marque too much of an advantage.
"I feel like the advantage that BMW was given in the beginning of the year was too much, this is my personal opinion," said Wickens.
"I think that they should have had one or the other, the fact that they were given the weight advantage and the rear wing was unreasonable and I think BMW used the politics of the series to their advantage."
"I believe they probably knew from the beginning that they didn't need both but they kept asking for both and it's a bit ridiculous.
"I mean, after the end of the year they claimed there is this car that's not competitive, they weren't gonna be strong and then they have the best car on the grid.
"It's just the fact now that they still have their minus 7.5 weight advantage and they are not even the lightest car on the grid, Audi is lighter than them so how can they say that they needed this advantage still? Then there's us that just driving around the tank."
Despite having led the championship three races ago in Moscow, Wickens is now 50 points adrift and will spend the penultimate round at the Hungaroring with the heaviest car.
"[Mercedes] is 1135 kg compared to BMW who are 1117 kg and then Audi 1110 kg, it's crazy.
"Before we even turn our lap, we are already five tenths slower than the Audi just on weight this weekend.
"The weights have done a good job this year, I think the fact there is an Audi, Mercedes and BMW fighting for the championship is a great thing - but I just feel like it would be a much different championship if BMW gave it a fair shot."