Fiance found guilty of murdering author as police re-examine death of first wife
Detectives are to investigate the sudden death of Ian Stewart's first wife after he was convicted of murdering his fiancee, children's author Helen Bailey.
The 56-year-old smothered the sedated Electra Brown writer and dragged her body into a cesspit as part of a plot to acquire her riches.
She was found in the foetid burial site beneath their garage three months after she disappeared in April last year.
Her pet dachshund Boris was also found dead in the cesspit.
Stewart was convicted of the "despicable" killing in a unanimous verdict at St Albans Crown Court, prompting police to turn their focus to the death of his first spouse.
Diane Stewart, an epileptic who was mother to his two sons Jamie and Oliver, was found dead in the couple's garden in June 2010. An inquest at the time concluded she died of natural causes.
Detective chief inspector Jerome Kent, who helped secure Stewart's conviction, said: "You will not be surprised that police investigating Ian Stewart for the murder of Helen Bailey would consider if there are any similar links to the death of his first wife. There is not a murder investigation into Diane Stewart, there is a re-examination of a sudden, unexpected death. It is only right that I would look back on somebody's past."
The former software engineer, wearing a light blue shirt and jeans, showed no emotion as he was found guilty by a jury of seven men and five women of murder, fraud, preventing a lawful burial and three counts of perverting the course of justice.
As he was led from the dock, he fixed his gaze on Jamie, his eldest son, who did not meet his eye.
Outside the courtroom, tearful relatives and friends of 51-year-old Ms Bailey embraced.
Her family welcomed the verdict, reached after five-and-a-half hours of deliberation, but said that her death had left them in a "long shadow of loss".
Stewart targeted the vulnerable widow on the internet in 2011, earning his way into her trust and later her £3.3 million estate after launching a "love-bombing" offensive.
"She was being grossly deceived by someone who was preying on her," prosecutor Stuart Trimmer told the trial.
Over many weeks, Stewart surreptitiously fed Ms Bailey his prescription anti-insomnia drug, zopiclone, possibly by slipping it into her morning scrambled eggs.
She soon became panicked by her deteriorating state of mind, searching online for terms such as "can't stop falling asleep" and expressing concern to loved ones.
A pillowcase found next to her body led the prosecution to suggest Stewart used a pillow to smother her while she was stupefied by the sedatives.
Ms Bailey, known for her young adult stories and memoir on bereavement, was found submerged in the tank of human sewage on July 15.
Her brother John sat in court almost every day of the trial, while their elderly mother Eileen broke down as she gave her evidence.
The family said in a statement: "Despite this victory for justice there can be no celebration. Our families have been devastated and nothing can ever bring Helen back to us, or truly right this wrong.
"A long shadow of loss has been cast over the lives of so many who will always remember Helen with enduring love and affection."
Stewart will be sentenced by Judge Andrew Bright today.