Medics have called for the head of the General Medical Council (GMC) to stand down over his handling of the case of a doctor who was struck off.
Dr Hadiza Bawa-Garba has won her bid to be reinstated over the death of six-year-old Jack Adcock in 2011.
Hospital doctors have said GMC chief executive Charlie Massey's position was "untenable".
The GMC said it was frequently called on to make tough decisions to protect patient safety.
Jack, who had Down's syndrome and a heart condition, was admitted to Leicester Royal Infirmary with vomiting and diarrhoea in 2011 and died 11 hours later from a cardiac arrest caused by sepsis triggered by pneumonia.
Prosecutors in a 2015 trial said Jack's death was caused by "serious neglect" by staff who failed to recognise his body was "shutting down" and close to death.
Dr Bawa-Garba said in her defence she had worked a 12-hour shift with no break and there was a lot of miscommunication in the ward.
She was convicted of manslaughter by gross negligence and sentenced to two years in prison suspended for two years.
Then in June 2017 Dr Bawa-Garba was suspended from the medical register for a year, but the GMC appealed against the decision and she was struck off in January.
However, she won her appeal to practise medicine again earlier this month.
The GMC's actions have angered doctors who said issues raised by the case, including understaffing, had been ignored.
The Hospital Consultants and Specialists Association (HCSA) union claimed doctors' confidence in the GMC had collapsed and called for Mr Massey's departure.
HCSA executive member Dr John West said: "The level of distrust and anger that we are seeing among hospital doctors has prompted begrudging apologies and a review into the laws surrounding such cases.
"Yet at no point has the chief executive of the GMC taken personal responsibility for his actions."
A spokesman for the GMC said it "recognised the anger felt by many doctors" about the case and fully accepted the Court of Appeal's judgment.
"We are frequently called upon to make difficult decisions, and we do not take that responsibility lightly," he said.