With more court cases being heard in Chinese, lawyers who know only English say the amount of work available for them has dropped, causing some to earn less, go into early retirement or move abroad.
Court cases were first heard in Chinese in the 1990s, followed by the introduction of a series of measures to promote a bilingual legal system. Since then, the use of Chinese in courts has taken off.
Judiciary figures show the proportion of criminal cases heard in Chinese has risen in recent years at all levels except the Court of Final Appeal, which always hears cases in English.
More than half of the criminal trials at the District Court and a third at the Court of First Instance were in Chinese, up from 14 per cent and 24 per cent respectively.
Civil cases in the High Court have shown the opposite trend. Some say the change is good as Cantonese is the mother tongue for the vast majority of the city's population. But the situation is taking a toll on lawyers who speak only English, especially those in criminal litigation.
"Some people saw it coming. A lot of people shut their eyes and they've been a bit shocked," barrister Keith Oderberg said. "We can't stop it, nor should we."
Oderberg said he knew of five lawyers who had left and four who had gone home to England, Australia and New Zealand and come back only when briefed to represent a client.
"They don't get the work, and because they don't get it, they leave, and that is to a very substantial degree because of language ability."
For those who remain, the workload has dropped. Oderberg estimated that among those lawyers with 10 to 20 years' experience who are unable to conduct litigation in Chinese, it has dropped 30 to 50 per cent.
Barrister James McGowan said it was "undoubtedly true there's a lot less non-Chinese work compared to 10 or 15 years ago". He acknowledged that other factors, such as high rents, had influenced decisions to leave or retire early.
But he said the decrease in work available in English and the high cost of translating Chinese statements and documents to allow for an English trial weighed heavily on lawyers' minds.
He said: "It is something which I think over a period of time will influence people's decisions on whether to go or stay." Judiciary figures show that 84 per cent of the 157 judges and judicial officers sitting at the end of last year were bilingual, up from 68 per cent of 155 in 2006.
There is no shortage of practitioners who can speak Chinese. Eighty-nine per cent of the 1,649 lawyers in the duty lawyer scheme and 79 per cent of the 3,050 on the government's legal aid panel can go to court in the language. The Law Society said most of its solicitors knew Chinese.
Some view the change as a positive step. Solicitor Christopher Morley said: "I have to accept I am living in a rarefied, privileged atmosphere where 99.999 per cent of the people speak Chinese, yet I can still go to court and address it in my mother tongue. Change is good and it is inevitable."
And McGowan added: "One shouldn't lose sight of the fact that there are many non-Chinese, hundreds of thousands of domestic helpers, people in the business community, visitors.
"There has to be a place for English-speaking lawyers for criminal law in Hong Kong to cater for the people who don't speak and read Chinese at all and those who, for various reasons, wish their cases to be heard in English, or be represented by counsel of their choice unfettered by language abilities."