Traffic **officers** have the authority to subject drivers to **drug detection tests** in different situations, including **preventive checks**. This means that even if a driver is not involved in an accident or does not show obvious symptoms of having consumed drugs, they may be required to take this test during a routine check.

- **Preventive tests:** Preventive checks are a measure to ensure that drivers are not under the influence of substances that could impair their ability to drive safely.
- **Test procedure:** To detect drugs, a saliva sample is taken from the driver and analyzed with a specific device. If the driver disagrees with the result, they can request a blood test to confirm it.

- **Legal consequences:** Driving under the influence of drugs is prohibited and can result in fines or even imprisonment. Therefore, it is important for drivers to undergo these tests when requested, as refusal can also lead to penalties.

In summary, officers can conduct drug detection tests during preventive checks to ensure road safety.