Three weeks later and this fast food worker is still in jail. I guess in the UK there is no "innocent until proven guilty" and that's why some left to form the USA a while back. This story couldn't occur in the USA.
Actually it can and does. If a judge compels you to turn over your password as a part of the discovery process and you refuse then you can be served with a contempt warrant and go straight to jail without trial and with limited possibility to appeal.
On December 17, 2006, defendant Sebastien Boucher was arrested on a complaint charging him with transportation of child pornography in violation of 18 U.S.C. ยง 2252A(a)(1). At the time of his arrest government agents seized from him a laptop computer containing child pornography. The government has now determined that the relevant files are encrypted, password-protected, and inaccessible. The grand jury has subpoenaed Boucher to enter a password to allow access to the files on the computer. Boucher has moved to quash the subpoena on the grounds that it violates his Fifth Amendment right against self-incrimination.
The district court held that Boucher could invoke the Fifth Amendment and refuse to comply.
They later worked around it by requiring him to provide the decrypted contents of the drive instead of the password itself since a border agent witnessed some of the files on the drive and he wouldn't be providing new evidence.
I'm not going to argue the rights and wrongs of the law, that's a different question. What is certainly true is that he has broken the law regarding providing the password when requested to do so by officers of the law following due process.
I repeat that I'm not arguing that the law is right. I'm merely pointing out that he is not innocent of the charges for which he is imprisoned.
I'm also pretty sure there are similar or analogous breaches of what one might call natural justice in the USA - I'm sure someone can provide examples.