But he later pleaded guilty to seven counts of making indecent photographs of a child and 10 counts of distribution.
None of the images were related to patients at the North Devon District Hospital where he was sacked from.
The Herald can reveal Walsh worked as a paediatrician in New Zealand in three hospitals in the Southern and MidCentral district health boards.
The Medical Council of New Zealand confirmed it was approached by the Devon and Cornwall Police in July last year, after Walsh was charged.
A council spokesman said Walsh worked as a paediatric registrar at Southland Hospital, then Dunedin Hospital, for 12 months each between 1996 and 1998.
He returned to the United Kingdom to complete his training in paediatrics, then came back to New Zealand as a specialist in August 2011.
On his return, Walsh worked at Palmerston North Hospital for 12 months before again returning to England.
The Medical Council spokesman said Walsh's registration remains current, but he has not held a practising certificate since September 2012.
He urged any patient, or their parents or guardians, who had concerns about treatment by Walsh to contact their local police station, or the MidCentral and Southern District Health Boards.
"The council will also work with and help the New Zealand Police in the event they undertake their own enquiries."
Chief medical officer for the MidCentral DHB, Dr Kenneth Clark, said there was no evidence that Walsh used his work computer inappropriately while he was employed there.
"No complaints were received regarding the care he provided, and no concerns were raised by patients or staff either during or following his employment."
Southern DHB chief executive Chris Fleming said Walsh worked at the hospitals 20 years ago but there were no records to suggest any concerning behaviour.
If any patients had concerns, Fleming asked them to contact the DHB or the police.
"No audit of his care or internet use has been undertaken, however if the NZ Police were to open an enquiry into Dr Walsh's time in New Zealand, we would of course provide any assistance that may be required.
"These findings against a former colleague are very disturbing, and our thoughts are with his victims, and all those impacted by his actions."
In sentencing Walsh in March to three years in prison, Judge Geoffrey Mercer said Walsh had gone to "considerable lengths" to disguise what he was doing.
"To state that your sexual interest in children, which underlines these offences, causes concern with regard to the position you held is a massive understatement," the BBC reported.
He added: "Your career is of course at an end and to quote from one of the letters you have written to me 'through my own actions I have lost my job, my career, my reputation and caused great harm to those around me that I love'."
Walsh was last week struck off as a registered doctor by the Medical Practitioners Tribunal Service, at a hearing where his conduct as "deplorable".
"He was dealing with vulnerable children and was in a position of considerable trust. The tribunal has noted the extreme nature of the abuse of the children depicted in the images."
The children in the films were between 1 year and 14 years old.
• Anyone with concerns about Walsh can contact their nearest police station and ask to speak with CIB staff, patient services at MidCentral DHB on (06) 350 8770 or Southern DHB on (03) 474 0999.
