The lawyer for a Hawke's Bay doctor on trial for drugging and sexually touching patients has said his client categorically denies the allegations.

David Lim is on trial at the Napier District Court on 13 charges of stupefying and indecently assaulting four Maori and Pacific Island male patients in 2014. 

The 41-year-old was working as a GP at The Doctors clinic in Hastings at the time.

The Crown alleges he gave each patient the sedative Midazolam and touched their genitals while alone in treatment rooms or toilet cubicles. The youngest complainant is a year 13 high school student, who first reported the incident to police.

LISTEN ABOVE: Newstalk ZB reporter Annette Hilton speaks with Larry Williams about the trial

It is said the patients were all suffering from only minor injuries when they visited Mr Lim, and three of them spoke very limited English.

Defence lawyer Harry Waalkens QC has told the jury that the drug used is well-known for causing hallucinations.

"That is feeling things, seeing things, hearing things that actually do not exist [and] did not happen."

He believes each patient would have recognised straight away that David Lim is an overtly gay person, and that the combination of Lim's sexuality coupled with the hallucination side-effect of the sedative has contributed to the misunderstandings.

Prosecutor Steve Manning also believes it’s not irrelevant that David Lim is gay.

He said Mr Lim breached the clinic’s protocols by giving each patient the sedative in question when it was completely unnecessary and while they were alone.

"And so while there were nurses who were volunteering to help recover a patient, or, a mother who could help and watch over her son - they were being encouraged to go away."

The Medical Council is worried current laws may be allowing other dodgy doctors to remain in contact with patients.

The group's tried three times in the last eight years, unsuccessfully, to get a law change that would allow it to immediately suspend doctors facing serious misconduct allegations.

Medical Council Chair Andrew Connolly said they feel it is something that needs to be looked at urgently, seeing it as a point of risk and a pretty straight forward law change to make.

Mr Connolly said it is "having a doctor still practicing who could be preying on patients that worries [the Medical Council] so much."