A British Muslim activist who was found guilty of willfully obstructing police by a UK court after he refused to hand over his mobile phone and laptop computer's pin number, says he is going to appeal against the decision.

Muhammad Rabbani, 36, was arrested at London's Heathrow airport last November and was charged six months later with obstructing police.

"I will be appealing this decision," Rabbani, who is the international director of CAGE, said in a statement on Tuesday.

"This judgement confirms that a person can fall foul of terrorism laws for protecting client confidentiality. The principle of presumption of innocence, the principle of client confidentiality and the principle of personal privacy are all too important to surrender even with the threat of conviction."

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CAGE, which was founded in 2003, is a nongovernmental organisation that advocates for individuals affected by British "anti-terrorism" legislation both within the country and abroad.

Rabbani said he refused to hand over the gadget to police because they contained sensitive information from an alleged torture victim of US security agencies.

He was ordered to pay court costs of $707 and was granted a conditional discharge of 12 months.

"This is a mockery of the concept of due process - the exercise of a principled, rational, truthful, justifiable concern that legitimate confidential obligations should be respected is transformed instead into a strict liability criminal offence," Gareth Peirce, Rabbani's lawyer, said.

Discriminatory enforcement

Rabbani was held under Schedule 7 of the Terrorism Act, which gives police a broad range of powers to search individuals at ports of entry without grounds for suspicion.

It has been frequently criticised by human rights groups for its allegedly discriminatory implementation and impact on civil liberties.

Under the powers UK police have, anything a person has on them can be confiscated, including communications and data storage devices.

The British civil liberties group Liberty has described the law as "breathtakingly broad and intrusive" and said ethnic minorities were disproportionately targeted with Asians 42 times more likely to be stopped than white people.

"We've long argued that Schedule 7 is ripe for misuse and discrimination," Liberty said on its website.

"We believe it contravenes the basic rights to liberty and respect for private life, as protected by the European Convention on Human Rights, and is therefore unlawful."

Last year, Tanzil Chowdhury of the University of Manchester's School of Law had told Al Jazeera the legislation was being used to "vilify" communities.

"Schedule 7 ... has been used disproportionately against Muslim, Asian and Black communities," he said.

"In recent Home Office statistics, drops in the use of Schedule 7 power were noted among all ethnic groups except for Asians which saw a two percent increase in the year ending September 2015.

"This has the effect of vilifying an entire community who have to continually answer the charge of its imagined criminality."

Alleged abuse of power

In an op-ed for Al Jazeera in May last year, Rabbani said: "What is clear from my experience is that authorities are trying to get a sense of an individual's beliefs.

"Not only is this a violation of the fundamental right to freedom of thought and belief, but there is no link between an individual's political and religious views and 'terrorism'. Yet this information is recorded and connections are drawn.

"There is no transparency at all about how the information gathered under Schedule 7 will be used. We don't know if it will be used to profile certain communities, or to design and develop policies, or to assist the state in criminal trials, or as secret evidence. We also do not know whether this information is shared with other agencies."

Alleged abuse of the power of Schedule 7 first came to international attention in 2013, when David Miranda, the partner of journalist Glenn Greenwald, was detained under schedule 7, also at Heathrow.

Miranda was held because authorities believed he was carrying filed relating to Edward Snowden, the US National Security Agency whistle-blower.

A British judge later ruled that authorities had acted lawfully.