The parents of Thomas Kingston, and his widow Lady Gabriella Kingston, endured an "utterly emotional inquest" on Tuesday 3 December, as the grieving widow said her husband died after making a "sudden impulse" decision to take his own life after suffering an adverse effect to prescribed medication.
Lady Gabriella, 43, joined Thomas' parents, Martin and Jill, at the inquest at Gloucestershire Coroner's Court, where the coroner acknowledged beforehand that it would be an "utterly emotionally exhausting" day for them all.
The financier died aged 45 from a "catastrophic head injury" and a gun was found near his body at his parents' home in the Cotswolds, on 25 February.
In a witness statement, Lady Gabriella said more people needed to be made aware about the side effects of medications to prevent this from happening to anyone else.
The inquest was told that Thomas had initially been given sertraline, a drug used to treat depression, and zopiclone, a sleeping tablet, by a GP at the Royal Mews Surgery, a practice at Buckingham Palace used by royal household staff, after complaining of trouble sleeping following stress at work.
He later returned to the surgery saying they were not making him feel better, and his doctor moved him from sertraline to citalopram, a similar drug.
In the days leading up to his death, Thomas had stopped taking medication, and toxicology tests showed caffeine and small amounts of zopiclone in his system.
Lady Gabriella's witness statement
In her statement, read out by Katy Skerrett, senior coroner for Gloucestershire, Lady Gabriella said: "[Work] was certainly a challenge for him over the years, but I highly doubt it would have led him to take his own life, and it seemed much improved.
"If anything had been troubling him, I'm positive that he would have shared that he was struggling severely. The fact that he took his life at the home of his beloved parents suggests the decision was the result of a sudden impulse."
She added: "The lack of any evidence of inclination it seems highly likely to me that he had an adverse reaction to the pills that led him to take his life.
"I believe anyone taking pills such as these need to be made more aware of the side effects to prevent any future deaths. If this could happen to Tom, this could happen to anyone."
Lady Gabriella described her marriage to Thomas as "deeply loving and trusting" and that he had never expressed any suicidal thoughts to her or others.
She added that he had been deeply affected by the suicide of a friend and the "devastating impact it had on other people's loved ones".
Thomas' father Martin "described his efforts to establish what might have made his son believe his life was not worth living," explaining that Thomas' actions were "entirely and fundamentally out of character".
The Telegraph's Victoria Ward, who was at the inquest wrote: "His parents, Martin and Jill, and his widow, Lady Gabriella Windsor, are in court. The coroner acknowledged that it would be an 'utterly emotionally exhausting' day for them all."
"Mr Kingston described his efforts to establish what might have made his son believe his life was not worth living. Many tears in court as he said it was so "entirely and fundamentally out of character" to take his life without careful planning while leaving so many loose ends."
"Thomas was a mature, well-adjusted, emotionally stable and mentally robust man," he said. "He had handled mentally challenging and difficult situations in the past." He said "it cannot be a coincidence" that he had started taking new medication three weeks prior."
Ms Skerrett concluded at the inquest: "Mr Kingston took his own life using a shotgun which caused a severe traumatic wound to the head.
"The evidence of his wife, family and business partner all supports his lack of suicidal intent.
"He was suffering adverse effects of medication he had recently been prescribed."
Thomas was the son-in-law of Prince and Princess of Michael of Kent. He married Lady Gabriella at St George's Chapel, Windsor Castle in May 2019.
In a joint statement with Thomas' parents Martin and Jill, and his sisters Joanna Connolly and Emma Murray, Lady Gabriella called her husband an "exceptional man who lit up the lives of all who knew him".
The financier's private funeral took place at the Chapel Royal at St James's in London, with the Prince of Wales among the mourners.
Lady Gabriella, who was last seen publicly at Royal Ascot in June, has moved back in with her parents at Kensington Palace.
The British writer, 43, previously lived in Notting Hill in west London with Thomas.
The couple were last pictured together on 14 February as they joined Queen Camilla at an engagement to celebrate the works of Shakespeare.
Who was Thomas Kingston?
Thomas and Lady Gabriella began dating after being introduced by mutual friends in 2014, with the financier proposing on the island of Sark in August 2018.
His career was broadly focused on finance, with a range of credentials including his most recent position as a director of Devonport Capital, which specialises in providing finance for companies in "frontier economies". But he started out in the Foreign Office, according to a previous entry on Devonport Capital's website.
In 2003, he became project manager for a "Government sponsored conflict resolution project" in Iraq.
According to The Telegraph, he was in Baghdad, working for the release of hostages after joining the Foreign Office's Diplomatic Missions Unit.
In 2006, Thomas joined Schroder's Asset Management in London before joining Voltan Capital Management in 2012 and five years later, he became a director of Devonport Capital Ltd.
He was a Bristol University graduate, having obtained a bachelor's degree in economic history, and a chartered financial analyst.
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