A teenager has been jailed for four months for refusing to give police the password to his computer.
Oliver Drage, 19, of Naze Lane, Freckleton, Lancs, had originally been arrested in May last year by a team of officers from Blackpool tackling child sexual exploitation.
His computer was seized but officers could not access material stored on it as it was protected by a 50-character encryption password.
Drage, who worked in a fast food shop, was then formally requested to disclose the password, but failed to do so.
He was convicted after a trial last month of failing to disclose an encryption key, an offence covered by the Regulation of Investigatory Powers Act 2000.
At Preston Crown Court he was sentenced to 16 weeks in a Young Offenders Institution.
Det Sgt Neil Fowler, of Lancashire Police, said: "Drage was previously of good character so the immediate custodial sentence handed down by the judge in this case shows just how seriously the courts take this kind of offence.
"Computer systems are constantly advancing and the legislation used here was specifically brought in to deal with those who are using the internet to commit crime.
"It sends a robust message out to those intent on trying to mask their online criminal activities that they will be taken before the courts with the ultimate sanction, as in this case, being a custodial sentence."
Police are still trying to crack the code on Drage's computer to find out its contents.