Doctors' leaders have attacked plans to lower the level of proof needed for a medic to be struck off.
The Shipman Inquiry raised concerns about medical regulation
The British Medical Association was responding to proposals from England's Chief Medical Officer Professor Sir Liam Donaldson.
The CMO set out his plans to change how doctors are regulated after the inquiry into GP killer Harold Shipman said the GMC was weighted in favour of doctors.
The proposals also include regular MoT-style checks on medics' abilities.
The plans are out for consultation until the end of November.
The BMA says it "opposes outright" the proposal to lessen the burden of proof required in fitness to practice cases from criminal standards - beyond all reasonable doubt - to civil standards - on the balance of probability.
Mr James Johnson, BMA chairman, said: "It cannot be right, when a person's entire means of earning a living is at stake, to rely upon a balance of probabilities rather than proof beyond reasonable doubt."
The BMA also rejects the idea of setting up an independent tribunal to judge when serious complaints are made against doctors.
It said in its response to the CMO: "Any transfer of adjudication from the GMC could only be properly considered once the credentials, funding and accountability of any new body were established."
The BMA criticised a proposal to remove responsibility for undergraduate medical education from the GMC to a new body called the Postgraduate Medical Education and Training Board.
And it says if "does not see any point" in a proposal requiring UK doctors and graduates of British universities to sit a language exam.
In its response to Sir Liam's document, the BMA says: "Throughout the report we found ourselves more often in sympathy with the identification of a problem, recognising the issues that needed to be addressed, rather than with the proposals suggested to deal with them."
The GMC has yet to publish its official response to the CMO's plans. But when the document was published in July, it said it was in favour of the MoT checks, but would have to "carefully consider" the other points.
When he launched his document, Sir Liam said: "Patients put their trust in doctors often at a major moment in their lives.
"They are right to do so, but my review has shown that the public and doctors think that this trust must be underpinned by a strong system to assure good practice and safe care."