Doctors at a new clinic in Canberra are about to practise in largely uncharted medical and legal terrain, offering patients confidential chemical analysis of illicit drugs along with advice and care designed to keep them safe.

Considered by some to be a controversial harm minimisation measure, the clinic is backed by funding from ACT Health.

But what happens if lives are in danger or if totally unknown substances are brought in? And will the police still be able to target those attending the clinic?

Dr David Caldicott, emergency physician and the Lead Clinician for Pill Testing Australia, explains.