Research has found the number of people charged for driving under the influence of drugs in New South Wales has tripled in the two years to June 2016.

Highest rates of drug driving convictions in NSW: 1) Richmond-Tweed 2) Sydney- Outer South West 3) Riverina 4) Capital Region 5) Southern Highlands and Shoalhaven 6) Central West 7) New England North West 8) Hunter Valley (excluding Newcastle) 9) Mid North Coast 10) Far West and Orana Source: BOCSAR, July 2015-June 2016

The NSW Bureau of Crime Statistics and Research (BOCSAR) report released today showed in the 2014-15 financial year, 2,331 drug-driving charges were finalised in the NSW Local Court. In the 2015-16 financial year, there were 9,808 charges.

BOCSAR director Don Weatherburn said the figures were largely a result of an increase in drug-testing.

"We know from previous research it's a combination of stronger policing and more frequent drug-driving," Mr Weatherburn said.

The figures also showed that 79 per cent of those convicted were men aged between 18 and 39.

"They're often picked up when they're doing other kinds of driving offences, but now that there's random drug-testing they're also picked up because police are checking for that sort of thing," Mr Weatherburn said.

The local area command with the highest rate of convictions was the Richmond-Tweed on the state's north coast.

The rate of 470 convictions per 100,000 people in the Richmond-Tweed is five times the state average.

"We know that drug-driving has been a problem up in that area for some time because we've conducted surveys of residents and asked them if they've been driving under the influence of drugs and those surveys have indicated quite a high proportion report having driven under the influence of drugs," Mr Weatherburn said.

"These figures reflect that, but they also reflect the heavy presence of police in the north.

"There are certainly some parts of the state that have rates of offending that are twice or three times the state average, but five times the state average probably sets something of a record."

Mr Weatherburn said the number of people charged with drug-driving in the Richmond-Tweed may actually be even higher, because approximately 20 per cent of convictions were unrecorded.

Nimbin Hemp Embassy president Michael Balderstone says cannabis users are being unfairly targeted by roadside drug-testing. ( ABC North Coast: Samantha Turnbull )

'It's very uncool'

Nimbin Hemp Embassy president Michael Balderstone, who has been campaigning for several years against roadside drug-testing in the region, said he was unsurprised by the figures.

Mr Balderstone said some cannabis users were turning to other drugs as a result of roadside testing.

"Cannabis stays in your blood or system for a month, maybe even two months, so anyone who has been around joints is going to come up [in test results]," he said.

"Nothing is upsetting people in the Northern Rivers more than this saliva testing — it's pushed people to use other drugs.

"All of the other illegal drugs are through your system in one or two days."

He said a heavy police presence was to blame for the increase.

"They're [the police] are picking on us and it's very uncool," Mr Balderstone said.

"It's actually seriously below the belt, very un-Australian I would call it."

He said tests based on driving ability should replace drug-testing.

"There has to be something better than this system," he said.

"It should be about impairment."