Life, Liberty and the Pursuit of Hippies

Sunday Canberra Times journalist Phillip Thomson undergoes random drug test performed by First Constable Brooke Crampton as part of the Cut The Toll campaign over the Christmas holiday period. The Canberra Times 26 November 2013 Photo Jay Cronan

Photo credit: Fairfax Media/Jay Cronan

The NSW police’s system of roadside drug testing (RDT) is a poorly justified encroachment on the freedoms of the individual. Similar to random breath testing, RDTs randomly screen drivers for marijuana, methamphetamine and ecstasy. But apart from the context in which these tests are carried out, there are few further similarities between RBTs and RDTs.

Strictly speaking, RBTs are an encroachment by government on our freedom to conduct our lives as we wish. The reasons why we never think of RBTs as a burden are because RBTs are a very minor inconvenience, and one that is very effective at taking dangerous drivers off the roads/preventing harm to others. Roadside drug testing lacks both these redeeming qualities. It is both inefficient (when it comes to resource allocation) and ineffective (when it comes to preventing harm to others).

The technology behind roadside drug testing is still emerging: because of this, a roadside saliva swab can take up to seven minutes. Apart from the time cost, the tests also have a disproportionately high fiscal cost – each test is worth at least $30 (compared to a few cents for each RBT).

Of course, high-cost government interventions are completely acceptable when the large burden is proportionate to a large benefit. The benefit that roadside drug testing should be providing is increased safety for other drivers. However, evidence has surfaced that the RDT screening process is largely unconnected to the safety of road users. I’ll take a moment to explain this.

In response to the government’s plan to increase the number of roadside drug tests next year, Greens MP David Shoebridge lodged a GIPA request for details of RDT police operations. The documents demonstrated that the saliva swap technology tests for the mere presence of drugs, but that the test is unable to tell how much of the drug is in the person’s system. This means that the test has little to do with the extent to which the driver’s ability is actually impaired: a driver could test positive for marijuana smoked up to 48 hours ago, even if that marijuana is no longer having an effect on the individual’s driving.

You wouldn’t think it (given the tone of this piece), but I am generally in favour of testing drivers for drug intoxication. What I am opposed to is the inefficient and ineffective RDT system that currently exists. The simple fact is, any government scheme that impinges on the lives of citizens ought to be rigorously principled. The approach to roadside drug screening should be based on the harm principle, which means that drivers should only be penalised where they test positive for a harmful amount of an inhibiting drug. A simple axiom should be applied; drug consumption that makes the road less safe for other drivers should be prohibited (note that this is the conclusion reached in the UK’s Wolffe report). The current roadside drug testing regime falls foul of this standard, and should be seriously reconsidered.