The Health and Disability Commission says the Medical Council should have responded more quickly to its warnings about an Auckland doctor with 16 complaints against him.
The Health Practitioners Disciplinary Tribunal has found Dr Ratilal Ranchhod guilty of professional misconduct for forgery and for treating patients without a valid practising certificate.
Deputy Health and Disability Commissioner Rae Lamb told Nine to Noon that her office had written several times to the Medical Council to warn them about the risk to the public.
However, she says it was not until December 2008 that Dr Ranchhod's practising certificate was cancelled.
"The process in this instance appears to have taken too long," she said.
Ms Lamb says while the commission has no jurisdiction over the Medical Council, it's expected that it will respond to warnings quickly and appropriately.
Health Minister Tony Ryall has asked for an urgent report into the case.
The Medical Council has declined to comment.
Dr Ranchhod was suspended and ordered to pay almost $28,000, a decision released on Wednesday by the Health Practitioners Disciplinary Tribunal says.
The tribunal said Dr Ranchhod managed a service, Housecall, that involved seeing patients in Auckland rest homes and in Auckland Prison.
It says his annual practising certificate hadn't been renewed, amid questions about his skills, but he continued to see patients between December 2008 and January last year.
He'd also altered his previous certificate to enable him to do this.
The tribunal suspended him for two months from mid-December 2009 and imposed conditions on how he worked when he resumed practising.