Speaking to reporters here, Gadkari said, "The CBI is being misused. The CBI and the judiciary are being used to blackmail Opposition parties. Such facts are coming to light."
He emphasised that BJP wants the country to have an "impartial and fair" judiciary as it is one of the pillars of democracy with legislature, executive and the media.
"The intention behind what Mamata Banerjee has said is that it is being seen that the judiciary is also being put under pressure by the government," Gadkari said.
Banerjee had last month said that a section of the judiciary is corrupt and that there are instances where court judgements have been bought for money.
Though the BJP has often attacked the CBI for being partial to the government and even termed it "Congress Bureau of Investigation", this is perhaps the first instance where the party has attacked the judiciary and said it bows under government pressure.