A health watchdog has gone to the High Court to challenge a General Medical Council decision not to strike off paediatrician David Southall.
Professor Southall arriving at the High Court
Professor Southall was barred from child protection work for three years after being found guilty of serious professional misconduct in August.
He had accused a man of murdering his two sons after seeing a TV documentary.
But the Council for Healthcare Regulatory Excellence said the GMC imposed an unduly lenient penalty.
Professor Southall was found guilty of professional misconduct after wrongly accusing solicitor Sally Clark's husband of murdering their children.
Monica Carss-Frisk QC, for the CHRE told Mr Justice Collins the penalty was "manifestly inadequate and inappropriate".
She said the GMC had "woefully failed" to "maintain confidence in the medical profession and send out the right signals to the public".
"If one looks at the other important objective of maintaining confidence in the medical profession and sending out the right signals, then we say the PCC [professional conduct committee] has woefully failed in that task ... and has sent out entirely the wrong message to the profession and members of the public".
The CHRE believes the only appropriate penalty is to erasure Professor Southall's name from the register of medical practitioners.
But the GMC is opposing the CHRE's challenge, and says striking off was not the only option.
Mark Shaw QC, appearing on behalf of the GMC, defended the PCC's decision not to "sacrifice" Professor Southall's "distinguished and outstanding" career as a paediatrician - despite his "Achilles Heel" in the field of child protection.
He said: "I am not prepared to accept that erasure is the only possible
But Mr Justice Collins suggested Professor Southall's stance revealed "arrogance".
"He has a belief, and he believes he is right, and he forms his belief on less than full material and he will not be swayed whatever the consequences".
The judge suggested those consequences "were potentially pretty ghastly, and actually thoroughly unpleasant because at the time they created a real difficulty for Mr Clark".
Sally Clark, from Wilmslow, Cheshire, was convicted in 1999 of murdering her two sons Christopher and Harry.
But that conviction was quashed when new medical evidence showing the babies died of natural causes was accepted at a second appeal hearing in January 2003.
The GMC hearing centred around conclusions Professor Southall drew after seeing an interview with Mr Clark on Channel 4's Dispatches programme broadcast in April 2000.
In his interview, Mr Clark described how the couple's first baby Christopher had suffered a nosebleed just 10 days before he died in December 1996.
Professor Southall told police he believed Mr Clark had killed the children after watching the interview, but without seeing any documents relating to the case or interviewing the family.
He later outlined his concerns in a report. It was submitted to the family court, which was considering who should take care of the Clark's third child.
The Clark family had called for the doctor to be removed from the register.
Ms Carss-Frisk told the High Court: "This is a case where Professor Southall has entirely failed to recognise in any way that what he did was wrong."
He maintained "to this day" the view he reached based largely on the television programme "is still right", said Ms Carss-Frisk.
She added: "He has at no time offered any apology or shown any insight, remorse or contrition".
The hearing continues on Friday.