A Sydney doctor deliberately injected his wife with a lethal dose of fast-acting insulin before spending the rest of the night with his new lover, a judge has been told.
Two days before the death of his wife, Brian Kenneth Crickitt had carried out Google searches on insulin overdoses, said prosecutor Mark Tedeschi QC in the crown's opening address on Wednesday.
And two days after her death, Crickitt was allegedly seen holding hands with his lover near the morgue where he had gone to inspect his wife's body.
Crickitt, 63, has pleaded not guilty in the NSW Supreme Court to murdering Christine Crickitt, 58, inside their Woodbine home in Sydney's southwest late on New Year's Eve or early on New Year's Day in 2010.
Crickitt was motivated to murder his wife, who was not a diabetic, so he could claim her life insurance worth $568,000 and be with his new lover, the prosecutor said.
The marriage had become "quite toxic" while Crickitt had developed an "intensely emotional relationship" with Linda Livermore, whom he had met at meditation classes.
"The accused had raised with Linda Livermore the possibility of them getting married," Mr Tedeschi said.
"She responded positively to this suggestion."
On December 31, the doctor saw a diabetic patient and allegedly later used a prescription he wrote for her to obtain fast-acting insulin from a local pharmacy..
The crown alleges Crickitt either forcibly injected the syringe of insulin into her buttock or lied to his wife about some medication and she agreed to the shot thinking it was a drug she legitimately needed.
After injecting the insulin, he remained in the house until she was dead, in a coma or semi-conscious, and then spent the rest of the night at Ms Livermore's home, Mr Tedeschi said.
An autopsy carried out on January 2 was unable to ascertain any cause of death.
Fast-acting insulin is not detectable in the blood after 24 hours.
"The crown case is the accused knew this and deliberately chose New Year's Eve to murder his wife knowing it was highly unlikely an autopsy would be conducted on New Year's Day," Mr Tedeschi said.
Secretly recorded conversations included Crickitt praying with his new wife, Julie Crickitt, saying: "Lord, this is a nonsense the police are coming up with."
Tim Gartelmann SC, for Crickitt, said the defence contended that insulin did not cause Christine Crickitt's death and there was no evidence the drug was a contributing factor.
"The defence case is that the cause of death in this case remains unresolved," he said.
Referring to the crown's alleged motive, Mr Gartelmann said Crickett had no financial difficulties and his affair was not a compelling reason to kill his wife.
Crickitt had no knowledge of conducting the insulin overdoses Google searches, but his occupation did not exclude him doing research for innocent purposes, he said.
The trial is continuing before Justice Clifton Hoeben without a jury.
