While some lawyers expressed concern that Britain was playing politics at the expense of Hong Kong’s judicial independence, others said it reflected some countries’ diminished faith in the city’s rule of law.

Cheng, a barrister by profession, argued that lawyers were bound by the so-called cab-rank rule under which they could not turn away clients based on their identity or the nature of the case. In the same manner that taxi drivers are not allowed to refuse fares, the rule ensures that even the most notorious criminals are given fair legal representation.

“The Bars in the UK and in Hong Kong take pride in their independence and take pride in our cab-rank rule,” Cheng said.

“The cab-rank rule is one of our very fundamental principles of the independence of the Bar that gives a strong and independent legal sector, which of course is also conducive to a stronger and independent judiciary.”

Without naming Raab, Cheng said: “The fact that certain high-ranking officials have uttered words such as ‘mercenary’ is, with respect, disgraceful to such a reputable counsel.”

Perry’s withdrawal was announced on Wednesday morning in a statement from the Department of Justice.

Former top prosecutor calls on UK foreign minister to apologise to David Perry

Last week’s news that Perry – who has served as prosecutor in some of Hong Kong’s highest-profile trials – would take on the case attracted a firestorm of criticism from politicians and activists back in his home country.

“I don’t understand how anyone of good conscience, from the world-leading legal profession that we have, would take a case where they will have to apply the national security legislation at the behest of the authorities in Beijing, which is directly violating, undermining the freedom of the people of Hong Kong,” Raab said in an interview with British media, mistakenly assuming it to be a national security prosecution.

The case against the nine opposition figures centres on an unauthorised anti-government protest march in Causeway Bay on August 18, 2019.

The defendants include veteran unionist Lee Cheuk-yan, organiser of the city’s annual candlelight vigil to commemorate the Tiananmen Square crackdown, and longtime activist “Long Hair” Leung Kwok-hung.

All nine were charged jointly with organising as well as knowingly taking part in an unauthorised assembly.

The trial was set for February 16 after the High Court granted the justice department’s ad hoc application to hire Perry from overseas on the grounds that the case would have a “real and significant impact on the exercise of the freedom of assembly in the future”.

Former director of public prosecutions Grenville Cross, who has demanded Raab apologise to Perry for calling him a “mercenary”, described it as “a setback for criminal justice and a sad day for the rule of law in Hong Kong”.

He accused Raab of using “the authority of his office to beat up on a distinguished British barrister” with a view to weaken the city’s legal system.

The British official had failed to get his facts straight, Cross noted, as the case in question did not concern national security as Raab had claimed.

“It will dismay everyone in Hong Kong who values the rule of law, as well as fair-minded observers,” he said.

University of Hong Kong associate law dean Simon Young Ngai-man called it a “shame”, praising Perry for his integrity and ability.

“Had he stayed on, we could be confident the prosecution would be handled competently, fairly and according to the highest standards of the Bar,” he said.

Critics have argued that the case was straightforward enough not to require the assistance of a top barrister from another jurisdiction.

Phil Chan, a human rights law scholar based in Britain, said Perry’s withdrawal stopped short of having an actual impact on Hong Kong’s legal system.

“However, criticisms that he received from politicians, judges and fellow barristers in the UK do suggest the extent of faith other countries have in the rule of law in Hong Kong despite the Hong Kong government’s public relations exercises,” he said.

Chan said Raab’s mistaken assumption that this was a national security case reflected how increasingly difficult and confusing it had become to tell such prosecutions apart, given the way in which the Hong Kong government and police were handling them.

Outgoing Bar Association chairman Philip Dykes said he did not expect Raab’s criticism to affect the robustness of the city’s legal system. He noted that Raab had not targeted either a local judge or a Hong Kong barrister subject to the cab-rank rule.

Dykes also pointed out that Perry was not obliged to take up a case overseas under the cab-rank rule.

“Overseas barristers are subject to no such constraints and are free to decline the offer of a brief if they find it unappealing, whether invited to prosecute or defend,” he said.

Law Society president Melissa Kaye Pang said the Basic Law, the city’s mini-constitution, required the Department of Justice to control criminal prosecutions free from interference.

“No one, be it from Hong Kong or overseas,should interfere or attempt to interfere with the independent prosecutorial process. It is important that legal practitioners should be free from political pressure in deciding whether to act in a certain case irrespective of one’s political views,” she said.