The city's top court dismissed the government's appeal against a ruling that it said wrongly restricted its power to lay misconduct charges against civil servants. The Department of Justice argued in the Court of Final Appeal that a lower court erred last year in finding that a civil servant could only be charged with misconduct in a public office if the offence would 'affect [the] public interest'. But five judges, in a unanimous judgment yesterday, upheld the lower court's ruling that the offence of misconduct in a public office was applicable only where the accused's job allowed them to exercise powers which affected the public interest. The appeal stemmed from the prosecution of Wong Lin-kay, a truck driver with the Agriculture, Fisheries and Conservation Department, who continued to drive at work despite losing his licence for a drink-driving offence. He was convicted on six counts of driving while disqualified and a charge of misconduct in public office, resulting in a 15-month jail term. But the misconduct charge was later quashed on the basis that his offence was not covered by that charge. Mr Justice Roberto Ribeiro said in the judgment that not every public employee was liable to prosecution under the misconduct charge. In the appeal hearing, Gerard McCoy SC, for the Department of Justice, said the Court of First Instance's judgment last year had made prosecutors' work difficult because it classified civil servants into two groups - those who hold power over public affairs, and those with little or no power. The ruling made it impossible to charge low-ranking civil servants with misconduct regardless of the seriousness of their offence, he said. But Ribeiro said that if McCoy's view of the offence was accepted, it would result in discrimination against public employees. It would mean an employee like Wong, who hid their disqualification from their employer, would receive different treatment depending on whether he worked in the public or private sector. 'The law would criminalise the conduct of the government employee notwithstanding that both drivers behaved in an identical manner. That is unjustifiable,' he said. He said Wong's misconduct did not represent an abuse of power because he had not been entrusted with any power. 'He was, as the [Court of First Instance] judge pointed out, simply a truck driver.' Lord Justice Millett said misconduct in a public office was easier to describe than to define. 'It covers a very wide range of disparate wrongdoing, and any attempt to produce a single all-embracing definition is likely to fail to include some particular instance,' he said. The charge should relate to an employee's actual function, he said. A department spokeswoman said the ruling had provided 'clear and useful guidance' on the application of the misconduct law.