The ACT should be guided by evidence, not unions, in introducing the nation's first needle and syringe program trial, experts say.

Australia needs to introduce needle and syringe programs in jails, say experts who lament the limited progress in setting up a trial.

They say only the Australian Capital Territory has shown leadership on the issue, but a proposed trial at the Alexander Maconochie Centre (AMC) may be doomed by the need for support by most prison staff.

Associate Professor Mark Stoove, head of the HIV and Justice Health Research programs at Melbourne's Burnet Institute, and other experts wrote an opinion piece in the Medical Journal of Australia.

Even though the prison programs are endorsed by many Australian and global medical and health bodies, only eight countries currently run them.

Australia is one of 74 countries that support needle and syringe programs in the community but not in prisons, a stand which the authors say constitutes a breach of human rights and international law.

People who inject drugs are grossly over-represented in Australian jails and up to 58 per cent of prisoners report lifetime injecting histories, the authors say.

The prevalence of blood-borne viruses, commonly transmitted through sharing injecting equipment, is also substantial in prison, with high rates of intra-prison hepatitis C transmission reported.

The authors said research and evaluation of prison programs showed no increase in drug use or availability, no reports of needles being used as weapons or safety problems associated with syringe disposal.

The Community and Public Sector Union (CPSU) had historically resisted prison programs, largely due to those concerns.

The ACT "must show the leadership lacking in other jurisdictions by allowing evidence and expert advice, rather than unions, guide public health policy", say the authors.