‘Poisoning for dummies’ Doctor accused of harming partner also questioned about first husband’s death

• Published date: 15 October 2023
• Author: Sam Sherwood
• Publication title: Herald on Sunday

The then 48-year-old builder looked across and claimed he saw his partner, medical researcher Dr Shelagh Dawson, wearing blue surgical gloves, with a syringe containing yellow liquid and her thumb on the plunger

He yelled out for the nurses to come, and alleged the retired epidemiologist dropped the syringe and scrambled to find it before the nurse entered the room.

Four months later he went to police alleging Dawson had attempted to murder him on three occasions.

Operation Medway was launched and Dawson was interviewed for three and a half hours.

The Herald on Sunday can now reveal the contents of the interview in which she denied poisoning Lewis at various points calling the allegations “ludicrous” and “spiteful”. She was also questioned about the death of her first husband, which she said was the result of “medical misadventure” after a routine colonoscopy.

Nearly five months later the 60-year-old took her own life.

Police were in the process of preparing the investigation file for formal review by the Crown Solicitor prior to her death.

A police summary report, obtained by the Herald on Sunday examined the case, revealing Dawson was believed to have attempted to change Lewis’ $500,000 life insurance policy into her name and had made a number of curious internet searches including “poisoning for dummies”.

Dawson met Lewis following her husband Graham Dawson’s death in 2009. At the time of his death, the couple had almost finished work on their home. She tried finishing it herself and amputated her thumb while using a table saw. She then arranged for Lewis, a builder, to help complete the job.

After Dawson sold her house she went to live in Perth for a couple of years. Once she returned she and Lewis went to the cinema together. Their relationship began in 2015 when he moved into her home on Medway St, Christchurch.

Lewis first thought something was astray in January 2017 when he arrived home to find Dawson “passed out” in bed. She claimed she had been hit by a car outside her home while she was bending down to look at a cat.

Police spoke to Dawson, but were unable to establish whether any such cars had been on her street at the relevant time, despite her providing information about the vehicle and the name of the company that owned it.

A search of her devices in 2018 revealed that on the morning of the incident, she had used her computer to search “how much do you get for being run over in NZ”.

Then on July 15, 2017, Lewis was admitted to Christchurch Hospital after Dawson phoned emergency services advising he was falling over and unable to walk.

According to the police summary report, when the ambulance arrived Dawson told the staff Lewis’ abnormal behaviour began about 2pm that day, and he had been working with a new product or chemical. The paramedic did not believe this was consistent with Lewis’ symptoms.

His initial thoughts were that Lewis had ingested drugs or had a head injury.

Lewis was treated for presumed inflammation of the brain, although there was no confirmed diagnosis. He was discharged on July 21.

Three days later Dawson called emergency services again to say Lewis had fallen out of bed and was unconscious.

The paramedic noted he had a bruise on his right eye and described him as agitated, confused, babbling, and displaying symptoms of someone who needed urgent antibiotics, as she believed he had sepsis.

Dawson said she had been home all day checking on him and when she found him he was unconscious and his condition had come on rapidly.

Lewis was admitted to ICU in an induced coma. His last memory was of the afternoon of July 22.

A nurse who cared for Lewis in ICU said after intubation Lewis was initially confused as to the date, however, this resolved quickly and was a “common side effect of sedation drugs”. The nurse said Lewis was not delusional or hallucinating when he was transferred to Ward 23, and said he had asked if it was possible he had been poisoned.

One of the nurses in Ward 23 said her assessment of Lewis was that he was drowsy, but orientated, and noted no confusion, other than to say at one stage he was forgetful and did not remember getting up for dinner the previous night.

Lewis told the Herald on Sunday that once he was released from intensive care his suspicions grew. He asked his sister to get him some bottled water as he didn’t want to drink water that Dawson had access to.

“I was very conscious of staying awake while she was there because I didn’t trust her, I didn’t know what she’d been up to.”

At one stage in the evening he saw Dawson standing beside a biohazard bin. When asked what she was doing she replied she was throwing out some receipts.

Later, while lying in bed, he felt something tug on his luer.

“I looked over and questioned her: what are you doing? She said she was just checking it.”

About an hour later he felt it again.

“I looked over and she had a syringe three-quarters full of yellow liquid with her thumb on the plunger ready to go. I yelled out to the nurses; she pulled it out and dropped it on the ground.

“The nurses came running — she was scrambling around on the ground trying to pick up the syringe, and I actually even had the foresight to say to the nurses ‘she’s got blue gloves on’.”

A nurse would later tell police that when she entered the room Dawson was sitting on the chair beside the bed.

Dawson said she “was just reaching for a pen on the ground and he thinks I have put something in his IV line”. The nurse checked his IV line and did not see anything out of the ordinary. She also did not see any pen.

The nurse suggested to Dawson that she leave. She did not search Dawson’s possessions for a syringe or pen. The nurse noted that Dawson was wearing gloves.

The following day, Lewis said, his sister came to visit him in hospital and he told her what had happened.

“[We] decided to brush it off with Shelagh and say to her that, oh yes, I was probably hallucinating considering I’d just come out of...