A driver accused of causing the death of a baby boy is to mount an insanity defence saying she had undiagnosed Alzheimer's disease, a court heard.

Five-month old Louis Thorold died in the collision on the A10 in Waterbeach, Cambridgeshire, on 22 January 2021 and his mother suffered serious injuries.

Shelagh Robertson denies causing death by careless driving.

Mrs Robertson, 75, of Stables Yard, Waterbeach, is on trial at Cambridge Crown Court.

Mrs Robertson was driving home from a supermarket when she turned into the path of an oncoming van on the A10 which forced it onto the pavement, hitting Louis and his mum, the jury was told.

Van driver Andrew Freestone saw both the pram Louis was in and his mother, Rachael Thorold "go up in the air" from the impact of the crash, the prosecution said.

The court was told Louis was declared dead on arrival at hospital and his mother suffered serious injuries.

James Leonard, representing Mrs Robertson, told jurors it was "agreed by any reasonable objective test the way Mrs Robertson drove on the day of the accident fell below the standard to be expected from a reasonable, competent driver".

"The issue in this case is whether or not Mrs Robertson was suffering from insanity as it's recognised by law," he said.

"The defence case is that Mrs Robertson had undiagnosed atypical Alzheimer's disease both before the accident and on the day, and that's what will lead to the conclusion that the defence of insanity is made out."

The jury were told by Judge Mark Bishop that for an insanity defence to succeed they must be persuaded that Mrs Robertson was suffering from atypical Alzheimer's disease at the time of the crash and that "as a result of that disease she experienced disrupted thinking".

He said this disrupted thinking could either be that as she drove the car she "didn't know what she was doing", or that she "didn't know that what she was doing was wrong by the standards of reasonable people".

Louis's parents Chris and Rachael Thorold sat in the public gallery and had placed a white soft toy elephant on a wooden ledge looking out over the courtroom beside Mrs Thorold.

David Matthew, prosecuting, said: "Obviously a competent and careful driver doesn't drive into the path of oncoming traffic which has the right of way without looking."

He said a witness who spoke to Mrs Robertson after the crash recalled she said "I just didn't see him coming."

He said that another witness described Mrs Robertson as "alert, agile" and "able to scoot across the Mazda and leave by the passenger door" after the crash.

The driver of the van, Mr Freestone, was described by the prosecution as a "careful and professional driver" who had tried to avoid the collision.

Another driver who witnessed the crash, Kaye Lewis, said in a statement read to the court that the van driver was "fighting the steering wheel but the van just kept going towards the pavement".

She said she remembered seeing Mrs Thorold's face and the "absolute terror of it when she saw the van" before she was "thrown... in the air".

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HM Courts & Tribunals Service

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