Suspicions fall on Christchurch medical researcher over poisoned partner and dead husband

Dr Shelagh Isabella Dawson died at her Richmond home on May 9.

A Christchurch medical researcher has died from a suspected suicide after police were investigating claims she poisoned her ex-partner.

Dr Shelagh Isabella Dawson, 60, a diabetes researcher, died at her Richmond home on May 9, Stuff reported.

Before her death, police had questioned her about the poisoning of her partner, after he collapsed three times and was rushed to hospital last year.

There are also suspicions she may have fatally poisoned her husband nine years ago.

After her current partner was hospitalised, it was found his blood contained five types of prescription medicine.

A large stash of drugs – described as "a suitcase full" – was also discovered at Dawson's home, Stuff reported.

The drugs were reportedly prescribed by her doctor for a number of conditions she claimed to have.

The Medical Council of New Zealand is now investigating.

After being discharged, the partner consulted lawyers and police discovered Dawson had taken out a $350,000 insurance policy on his life.

The couple had been together for about three years before they split last year.

Detectives interviewed Dawson twice before her death, Stuff reported. She was also under investigation by ACC and another agency over benefit fraud.

Police found the partner's symptoms were almost identical to those suffered by Dawson's husband Graham Edward Dawson, 54, before he died in 2009.

Her husband's insurance company paid her $350,000 and she claimed a widow's pension from England. The couple had been married for 32 years.

Police today refused to comment on the investigation, dubbed Operation Medway.

People close to Dawson today declined to comment when approached by the Herald.

University of Otago, Christchurch confirmed that Dawson, a nurse with a PhD gained in the United Kingdom, was employed at the University of Otago's Christchurch campus between November 2004 and March 2009.

During her employment with the university, she was "not in positions with direct contact with patients, research subjects or medication", a spokeswoman said.

"Her first role with the Christchurch campus was as a research fellow with the New Zealand Health Technology Assessment group," the spokesman said.

"In her role with this now-defunct group, Dawson reviewed data relating to the prevalence of common conditions. She reviewed non-identifiable large data sets not individual patient records, and had no patient contact."

Dawson's second role at the university was as a lecturer of postgraduate nursing students. In that role, she gave lectures to nursing students and assessed their assignments.

A spokesperson for the coroner's office confirmed the Dawson case was active and investigations were continuing.