A doctor accused of misdiagnosing hundreds of children with epilepsy has begun a legal challenge after his work was labelled "seriously deficient".
Dr Andrew Holton gave wrong diagnoses of epilepsy to 618 children in Leicestershire between 1990 and 2001.
The General Medical Council ruled his professional performance was deficient but allowed him to continue working.
He has taken his appeal to the High Court in London, claiming the ruling was unfair and unlawful.
Regular checks
Dr Holton was suspended by the University Hospitals of Leicester NHS Trust in May 2001.
In January 2006 the GMC's Fitness to Practise Panel ruled the consultant paediatrician should be retrained, have regular checks by superiors, should not work with children and should work in a new speciality.
But on Monday his counsel Mary O'Rourke told the High Court the panel which heard his case "lacked competence" and went against the advice of experienced medical assessors.
She argued there was no proper evidential basis to support the panel's statement that Dr Holton had made frequent serious errors which justified disciplinary action.
Parents 'outraged'
The GMC is opposing the appeal, pointing to the "considerable public disquiet" over what was perceived as his "over-diagnosing" of epilepsy in young children.
Parents of children who were Dr Holton's patients said they were "outraged" by his appeal.
Mary Peberdy of the Leicester Epilepsy Concern Parents and Carers' Group said: "We believe our children have been permanently damaged as a result of Holton's actions and treatment as a doctor.
"We feel completely left out of this process and marginalised by the GMC. Who will protect our rights as patients if not the GMC?"
The appeal is expected to last two days.