A woman who was at the Royal Cornwall Hospital in Truro for an appointment had a shock when she saw her car being driven out of the car park by a stranger.
She shouted to a security guard and the car stopped, and two people got out and ran away.
The driver gave himself up to the police later after an appeal had been published in the press.
At Truro Magistrates’ Court Jake Thomas Doncaster, aged 23, of Cuth Avallon, Truro, pleaded guilty to driving a vehicle knowing it had been taken without consent, and to using it without insurance.
Alison May, for the CPS, said the owner of the car had been inside the hospital for her appointment and had left her coat, with the keys in it, unattended while she used the facilities, only to return and find it missing.
She went to the car park with a security guard and they saw her car being driven towards the exit.
Doncaster told the police he had gone to the hospital to buy a drink in the shop. “It was an opportunistic moment,” he said. “It was a stupid thing I did. I did not have any intention to steal it.”
He had previous convictions.
The case was adjourned for a probation report.