Speaking at the International Criminal Law Reform conference in Dublin, Justice Kirby said governments that had focused on educating rather than punishing those with HIV or AIDS were most successful in containing their spread.

''Those countries that have adopted a human rights-respecting approach to the HIV/AIDS epidemic have been far more successful in containing the spread of HIV than those countries that have adopted punitive, moralistic, denialist strategies, including those relying on the criminal law as a sanction,'' he said.

Justice Kirby has been heavily involved in the international fight against AIDS, having served as a member of the World Health Organisation's Inaugural Global Commission on AIDS from 1988 to 1992. Since 2004 he has been a member of the UNAIDS global reference panel on HIV/AIDS and human rights.

While many developed countries, including Australia, had laws that criminalised the deliberate spread of HIV, such laws should not be used as part of the strategy to curb infection rates.

''Legal and punitive laws have been kept in reserve because their aggressive deployment has generally been seen as counterproductive.

''This is so because of the typical ineffectiveness of criminal law as a response to activities important to individual identity and pleasure [such as sex and drug use].''

Justice Kirby, who is openly homosexual, spoke about his indirect experience with HIV, having seen friends die from the virus.

''From 1985, I lost a number of close friends, several of them members of the legal profession. I witnessed the substantial helplessness of the medical profession in the early days of HIV.''

He urged the thousands of lawyers, judicial officers and lawmakers from all over the world at the conference to avoid enacting what he called ''HILs'', or highly inefficient laws.

Of concern were laws introduced in some African nations, including Benin, Guinea, Guinea-Bissau, Mali, Niger, Togo and Sierra Leone, that impinge on the human rights of those infected with HIV or AIDS.

One law criminalised the ''wilful transmission'' of HIV, but defined the offence as the transmission of HIV ''through any means by a person with full knowledge of his or her HIV status to another person''.

Justice Kirby said, ''Potentially, [that law] imposes criminal liability, although a person may practise safer sex which reduces or eliminates actual risk of transmission to a sexual partner; takes steps to disinfect injecting or skin-piercing equipment; or involving mother-to-child transmission of HIV regardless of the actual risks involved in the particular case.''

He urged governments to introduce laws and programs that were proven strategies in the war against HIV and AIDS, even if they were unpopular with their cultures.

''Taking the effective measures is not always popular. Yet taking punitive measures, depending on their terms and enforcement, is, on current information, unlikely to succeed in the environment where there is no effective vaccine and no curative therapy which can be offered to persons living with HIV and AIDS.''