By Glenn Dobson, CEO, The Drug Detection Agency Group
The Governments introduction of roadside drug testing in New Zealand has triggered widespread discussion, debate, and assumption. For many employers and workers, the question has quickly become: “If Police can test this way on the roadside, why can’t workplaces do the same?”
It is an understandable reaction, but it is also a dangerous oversimplification.
Because while roadside drug testing and workplace drug testing share a common objective, safety, they are fundamentally different systems. Treating them as interchangeable risks undermining fairness, legal defensibility, and, ultimately, trust.
Safety Is the Destination — Process Is the Difference
Both systems exist because drugs increase risk. On roads, that risk is immediate and highly visible, impaired driving, delayed reaction times, serious crashes, and fatalities. The consequences are often sudden and irreversible.
In workplaces, risk manifests differently, but it is no less significant. In safety-critical environments, it may present as incidents, near misses, equipment damage, or serious harm events. These risks are well understood and rightly taken seriously. However, drug-related risk does not end at the factory gate, the construction site, or behind the wheel of a vehicle.
In white-collar, professional, and corporate environments, the impacts are often quieter but more insidious. Impaired judgement, reduced concentration, slower cognitive processing, and increased error rates can undermine decision-making at every level of an organisation. This can lead to flawed advice, financial miscalculations, data mishandling, compliance failures, and process inefficiencies that compound over time rather than announce themselves in a single incident.
For these organisations, the consequences are not measured solely in injuries, but in brand protection, reputational damage, regulatory exposure, and loss of trust. A single impaired decision in a boardroom, trading floor, control room, or professional services environment can trigger cascading consequences, client disputes, regulatory scrutiny, failed projects, or public reputational harm that far outlasts the original error.
This is why drug risk is not just a frontline safety issue. It is a governance issue. A risk-management issue. And increasingly, a business-critical issue tied directly to organisational credibility and resilience.
Enforcement vs Risk Management
This is where the distinction between roadside and workplace testing becomes critical.
Roadside drug testing is an enforcement tool. It is designed for speed and practicality in uncontrolled environments. Police operate under specific legislative authority, making rapid decisions to protect the public and support compliance and deterrence. Each test is a discrete event, focused on a single moment in time.
Workplace drug testing is something else entirely. It is a structured, longer term risk-management system designed to protect people and organisations over time. It is not just about whether a result is positive or negative on a given day, it is about understanding patterns, trends, and emerging risks.
Through TDDA’s electronic reporting platform, Imperans, employers can move beyond one-off testing and take a more informed, proactive approach. This includes the ability to:
- Track drug results over time
- Identify emerging patterns and hotspots
- Understand risk profiles across roles, sites, and regions
- Use data to inform policy, education, and targeted interventions
This is a fundamental difference. Roadside testing responds to an individual incident. Workplace testing, when done properly, becomes an ongoing partnership focused on prevention, insight, and continuous risk reduction.
Breadth of Screening: Narrow Enforcement vs Broader Risk Coverage
Another critical distinction lies in what is actually being screened. Under the current roadside regime, Police are screening for four drugs: THC, methamphetamine, MDMA, and cocaine. This reflects a legislative and operational decision to focus on a defined set of substances for roadside enforcement purposes.
In workplaces, risk profiles are broader, and so too must be the response.
TDDA’s verified workplace testing devices enable screening for up to nine drug types (and even more in hair testing), depending on the testing method and client requirements. This broader coverage reflects the reality of modern drug use and provides employers with a more comprehensive and defensible risk-mitigation framework.
One Method vs the Right Method
The new roadside drug testing regime relies solely on oral fluid testing, chosen for its practicality in the challenging roadside conditions Police need to work within. In that context, and with the challenges faced by the Police, a single testing matrix makes sense.
Workplaces, however, operate in far more varied and complex environments, and that demands a far more considered approach. The challenge is that there is no single “best” drug test for all workplaces. The beauty is that unlike the Police, workplaces have a choice. Each testing matrix, oral fluid, urine, lab based or hair, has different strengths, limitations, and appropriate use cases. Choosing the wrong method for the wrong situation can undermine both safety outcomes and legal defensibility.
This is why workplaces need to be very careful to select the right testing matrix for their specific circumstances. Factors such as the nature of the work, safety sensitivity, workforce profile, risk exposure, any identified drug issue, regulatory environment, and the purpose of testing all matter. A transport or construction environment may prioritise different risk indicators than a professional services firm, manufacturing site, or corporate office. A pre-employment screen raises different considerations than post-incident, reasonable cause, or random testing.
TDDA offers oral fluid, urine, lab based and hair testing precisely because each workplace is different. Some organisations appropriately choose urine screening over oral fluid screening due to its longer detection window and alignment with their risk profile. Others adopt a mixed model, using oral fluid testing in certain scenarios, and urine testing for others. In some cases, hair testing is incorporated to provide a longer-term view of substance use patterns.
The value lies not in defaulting to a single method, but in selecting the best tool from the toolkit, and applying it thoughtfully, consistently, and in line with standards and the workplace drug & alcohol policy. This is a critical distinction between roadside and workplace testing. Roadside testing applies one method to one moment in time. Workplace testing, when done properly, applies the right method to the right risk, as part of a broader, defensible safety and risk-management framework.
New Law vs a Proven Framework
Roadside drug testing in New Zealand is new. As with any new regulatory regime, it will evolve. Operational guidance will be refined. Thresholds may be adjusted. Case law will shape how the regime is applied in practice.
Workplace drug testing has already travelled this path.
It has operated for decades across safety-critical and professional sectors, informed by scientific evidence, legal challenge, and real-world experience. The standards underpinning workplace testing exist precisely because mistakes, shortcuts, and poorly designed systems have been tested, and found wanting.
A Critical Line Employers Should Not Cross
Perhaps the most important distinction is this: roadside testing is backed by the authority of the state; workplace testing is guided by standards, employment law, privacy obligations, and human rights.
In the workplace, a drug test result can alter someone’s career or employment trajectory. That reality demands a high level of procedural care. Any employer tempted to borrow roadside concepts without understanding this difference is not modernising their safety approach; they are increasing their risk exposure.
The danger is not roadside drug testing itself, it can be argued that the process is entirely appropriate for the circumstances. The danger is the assumption that all drug testing is now the same. It isn’t. Roadside testing responds to a moment in time. Workplace testing governs risk over time. One enforces compliance; the other builds safety, insight, culture and trust.
If the introduction of roadside drug testing tells us anything, it is this: drug risk in the community is real, visible, and increasing. That reality does not reduce an employer’s responsibility, it amplifies it.
Workplaces do not need to confuse their wants and needs with the new roadside regime. What they need is testing that is broader, smarter, and proportionate to the risks being managed. Testing that is defensible, data-led, built for the long term and fit for purpose. Because behind every policy, process, and test result is a human outcome.
At TDDA, we often talk about protecting the girl on the bike. Not as a slogan, but as a reminder of why safety systems exist in the first place. She might be a worker heading home after a long shift. She might be a member of the public sharing the road. She might be someone whose life is changed forever by a single impaired decision made somewhere else.
Roadside testing plays an important role in protecting her in that moment.
Workplace drug testing, done properly, protects her long before that moment ever arrives, by managing risk upstream, inside organisations, where patterns can be identified, behaviours addressed, and harm prevented, because workplace risk rarely stays confined to the workplace.