The declaration by High Court judge Michael Hartmann that certain provisions of the Crimes Ordinance are unconstitutional is a landmark for the rights of the individual guaranteed by the Basic Law of Hong Kong and the Bill of Rights.
It also affirms unambiguously the duty of the courts to strike down laws that are not consistent with guaranteed rights.
The government failed in an argument that the legislature had a right, in the democratic process, to make laws that overrode the constitutional rights of the individual in certain circumstances. These included protecting people vulnerable because of their youth, for example by prohibiting adolescent homosexual activity on moral grounds alone.
An application was brought before the court by a 20-year-old gay man, William Leung, for a judicial review of laws that he claimed discriminated against gay men. It was not because he had been prosecuted for any criminal offence.
He argued that provisions that permit heterosexual and lesbian couples to engage in sex once they have turned 16 discriminate against gay couples by prohibiting the same acts by consent until they are 21. His lawyers sought a declaration that sections of the ordinance were inconsistent with constitutional guarantees of equality before the law and the right to privacy.
The application was opposed by the government, which left itself with a difficult case to argue after conceding that three of four provisions cited by Mr Leung were indeed unconstitutional. This concession was noted as significant by Mr Justice Hartmann, who said each of the three discriminated against homosexuals and arbitrarily interfered with their right to self-autonomy in private.
But the government did not concede that a fourth provision making it unlawful for a gay couple to have intercourse with each other if either was under 21 was unconstitutional, or that it infringed their right to privacy. (The offence carried a sentence of up to life imprisonment). It argued that it was for the legislature to determine how best to protect young people and that the courts should defer to it. Its counsel argued that the legislature was in a better position than the courts to judge the prevailing 'social norms and values'.
Mr Justice Hartmann said that in matters of 'high constitutional importance' the courts were obliged to give 'considerably less deference to the legislature than would otherwise be the case'. The two constitutional rights upon which Mr Leung relied - equality before the law and his right to privacy - were recognised in the Hong Kong jurisdiction as fundamental human rights. Drawing on a recent British legal precedent, he described them as 'rights which belong to individuals simply by virtue of their humanity, independently of any utilitarian calcula- tion'.
The judgment does not amount to a rebuff of the post-handover government or Legislative Council. The provisions were passed years before the handover, in 1991, and have almost certainly become an outdated reflection of community values. As Mr Justice Hartmann said, no evidence was put before him to demonstrate what today - if it could be ascertained - was the prevailing view of the community towards private, consensual homosexual activity. In a cosmopolitan society 'social norms and values' changed rapidly.
The real significance of the judgment is that it upholds the core value of the Basic Law and the Bill of Rights - the constitutional guarantees of individual rights and freedoms. Constitutions are not set in stone. But the guarantees of our rights are. There is nothing wrong in principle with occasional suggestions of changes to the Basic Law to meet changing circumstances, when absolutely necessary and with the support of the people. But provisions concerning our city's high degree of autonomy and way of life - including our rights and freedoms - are the core of a solemn promise to the people of Hong Kong - and off-limits.