The doctor at the centre of the MMR row paid children £5 to take their blood samples at his son's birthday party and joked about it afterwards, a disciplinary panel heard today.
Dr Andrew Wakefield showed "callous disregard for the distress and pain" he knew or ought to have known the children might suffer as a result of his actions, it was alleged.
The Legal Aid Board provided him with £50,000 for research to support legal action by parents who believed their children were harmed by MMR, it was claimed.
The 50-year-old appeared before the General Medical Council (GMC) Fitness to Practise Panel in central London to hear the catalogue of damning disciplinary charges against him.
His wife Carmel accompanied him on the first day of the hearing, which is expected to last several months, while a core of supporters spent the day protesting outside.
Dr Wakefield, who now lives and works in Texas in the US, is charged alongside professors John Walker-Smith and Simon Murch.
The trio, who deny serious professional misconduct, published a paper in The Lancet medical journal in February 1998 suggesting there could be a link between the triple jab, bowel disease and autism.
It led to falling numbers of parents immunising their children and a row over whether the then prime minister Tony Blair had vaccinated his son Leo.
The central allegations against the doctors relate to investigations for their study on 12 youngsters with bowel disorders carried out between 1996 and 1998.
At the time, all three were employed at the Royal Free Hospital's medical school in London, with honorary clinical contracts at the Royal Free Hospital.
Dr Wakefield's behaviour at his son's birthday party allegedly took place at some point before March 20 th, 1999.
Among the 46 allegations, Dr Wakefield was accused of allowing one patient - known as Child 10 - to be given an experimental drug, known as "Transfer Factor", with the view to it becoming a measles vaccine.
He admitted being involved in proposals in 1998 to set up a company - Immunospecifics Biotechnologies Ltd - to manufacture the drug, with the intention that the father of Child 10 become its managing director.
Several Royal Colleges and faculties signed a statement ahead of today's hearing, saying there was no evidence of a link between MMR and autism.
Among signatories are the Royal College of Paediatrics and Child Health, the Royal College of General Practitioners, the Royal College of Pathologists, and the Royal Society of Medicine.