Questions remain about a drug initiative that could keep 20,000 people out of court each year, an advocate says.
Since February 29, people caught with low levels of MDMA, cocaine, ice or heroin in NSW can be spared a court appearance.
The Early Drug Diversion Initiative allows first- and second-time offenders to be issued an on-the-spot $400 fine, which can be waived if they complete a free counselling session led by a health professional.
But clarity was lacking on how the bipartisan policy would operate in the real world, Uniting NSW/ACT advocacy manager Emma Maiden said.
Police discretion in the long-running cannabis cautioning scheme has led to more non-Aboriginal adults and those living in affluent parts of Sydney receiving cautions, rather than court dates.
"There are certainly some positive aspects of the (new) scheme but there remain some important, unanswered questions and concerns," Ms Maiden said on Monday.
Those included whether police would test the drugs they seize, how they will determine on the spot whether something was under the drug supply threshold and how alleged offenders would be treated if testing later revealed they had "crushed Panadol" or another legal substance.
Knowing how police area commanders were instructing their officers was "critical to the scheme being applied without bias - which we know exists" and the impact of the laws on the most vulnerable, Ms Maiden said.
NSW Police declined to detail how local area commanders have been instructing officers and whether alleged drugs would be tested to back up infringement notices.
"Internal communication has been distributed to NSW Police officers regarding the Early Drug Diversion Initiative," a spokeswoman told AAP in a statement.
A drug criminal infringement notice can be issued when officers identify a low-level drug offence, she said.
"A person can pay the fine, elect to undertake a brief intervention in relation to their drug usage, or have the matter heard and determined by a court," the spokeswoman said.
Adults caught with supply quantities of illicit substances are ineligible for the scheme, as are the growing population of Australians using ketamine, a dissociative anaesthetic, recreationally.
But Ms Maiden said the scheme was bipartisan recognition that the 23,000 people arrested each year for drug use or possession and 19,000 sent to court would be better served by interacting with a health service.
The scheme also won support from defence lawyer and former police prosecutor Craig Murray, who said it was a welcome step forward in evidence-based policy in criminal justice.
But it could not be the end of the road.
"We still need the government to invest much more in drug and alcohol programs around the state particularly in regional areas," he told AAP.
"My hope is that when the premier holds his drug summit (in the second half of 2024), NSW can look at further practical measures to ensure that drug dependency is treated much more as a medical issues and further support given to people to turn their lives around."