A man has been convicted under counter-terror laws for refusing to hand over the passwords to his iPhone and MacBook during police questioning at Heathrow Airport.

Muhammad Rabinni, 36, was found guilty of wilfully obstructing an investigation by officers who wanted access to his devices when he returned from Doha, the capital city of Qatar.

He was found guilty by a judge at Westminster Magistrates Court on Monday for refusing to hand over the information to officers from the Metropolitan Police.

Rabinni is a director of CAGE, an advocacy group which campaigns against terror legislation. The group was widely criticized when one of its directors called Mohammed Emwazi – aka ISIS executioner Jihadi John – “a beautiful young man.”

Rabinni was stopped at Heathrow on November 20, 2016, when his flight landed, and questioned under powers officers can use to question people they suspect of being linked to terrorism.

In court, Rabinni argued that he should not have to give police access to his devices because they contained sensitive documents given to him in confidence by a man he described as a victim of torture by the US government.

The court rejected his argument, saying it was not a valid defence under the law. Journalists and lawyers have certain protections linked to privileged material, but neither applied to Rabinni.

According to the BBC, District Judge Emma Arbuthnot dismissed Rabbani's defence and said he took a "calculated risk" in refusing to hand over the information, which had previously paid off.

He was asked to pay £620 in costs and fees, and was given a conditional discharge, meaning he will go unpunished so long as he commits no crimes for the next 12 months.

However, it remains to be seen whether he has succeeded in protecting the information from police.

Scotland Yard still has his phone and laptop, and said in a press statement that the force is "continuing its efforts to examine the contents."

Dean Haydon, a senior Met Police counter-terror officer, responded to the conviction, saying: "It's crucial that police are able to use the legislation that exists to help keep the public safe."

A statement from Rabinni, published on CAGE's website, characterised the airport stop as "a digital strip-search" and said his conviction is proof that the law needs to be changed.

"I want to thank my lawyers and supporters who were here for me today. Of course, the decision is not one that we had been hoping for, but the judge understood and expressed this case is complicated," he said.