James Craig is led away after being sentenced to life in prison./SCREENGRAB
A US dentist who poisoned his wife has been sentenced to life in prison without parole after a Colorado jury found him guilty of murder and other charges.
James Craig, 47, had been having an affair when he plotted to kill his wife Angela Craig, in March 2023.
After lacing his wife's protein shakes with arsenic, he gave her a fatal dose of cyanide while she lay ill in hospital, prosecutors said.
Prosecutors also argued during a two-week trial that the dentist felt trapped in his marriage but was facing financial troubles and did not want a divorce.
Defence lawyers had argued that Angela Craig, who was then 43, died by suicide because she was heartbroken about her husband's "constant" affairs.
However, the Arapahoe County coroner determined that she died as a result of cyanide and tetrahydrozoline, a chemical used in eye drops.
Evidence showed James Craig searched for phrases including "how many grams of pure arsenic will kill a human" and "is arsenic detectable in autopsy?" and had a shipment of potassium cyanide delivered to his dental practice.
Two days later, Angela Craig drank a protein shake that made her feel dizzy and weak, and she was admitted to a hospital in suburban Denver.
Footage from a security camera showed the dentist holding a syringe before entering his wife's hospital room. Her condition rapidly deteriorated, and she was declared brain-dead several days later.
The jury found Craig guilty of first-degree murder on Wednesday, along with other charges including solicitation to commit murder - resulting from his attempts to get a fellow jail inmate to kill a detective working on the case. He was acquitted of manslaughter.
One of the couple's six children delivered a victim impact statement.
"I was supposed to be able to trust my dad," Miriam Meservy said, according to US news reports. "He was supposed to be my hero, and instead he'll forever be the villain in my book."
Arapahoe County District Judge Shay Whitaker sentenced Craig to life in prison without the possibility of parole for the murder charge, plus 33 years for the additional counts.
"This is Angela's husband [poisoning] her, causing her to die a slow death," District Attorney Amy Padden told reporters at a news conference following the sentencing. "It wasn't something done in the heat of passion. It was deliberate.
