Jonathan Ochola, admitted being at home watching television when his friend Rashad Delawala committing theft in the Ladbrokes shop in Southsea, Hants, England.
But in reality, the 21-year-old boy is the driver of the theft and they divided the loot alone.
Police also found evidence that Ochola involved in the theft after finding a diary that describes in detail about the theft.
"We never get such evidence. Dumbest thing to do to write a theft in his diary," said Detective Constable Mel Sinclair as reported by the Telegraph on Monday (11/07/2011).
"Ochola himself realized that it was the dumbest thing to do," he added.