Brazil expands Lei Seca to detect drug use during traffic stops

Brazil is updating its Lei Seca regulations to allow traffic officers to detect both alcohol and psychoactive drugs during roadside stops.

This expansion marks a significant shift in road safety enforcement. By identifying drivers under the influence of illegal substances or prescription drugs, authorities aim to reduce traffic accidents and increase overall road safety.

Carlos Augusto Elias, a master in transport engineering from UFPE, said the new framework incorporates advanced devices such as the "drogômetro" and passive breathalyzers. These tools allow officers to screen for a wider range of impairing substances beyond ethanol during routine checkpoints.

The initiative comes as the Lei Seca law reaches 18 years of existence ^[1]. The updated enforcement strategy is designed for implementation across the entire Brazilian territory. For example, the system could be applied to drivers traveling long distances, such as a 300-kilometer route between Campos dos Goytacazes and Nova Iguaçu in the state of Rio de Janeiro ^[2].

Passive breathalyzers differ from traditional tests by detecting alcohol molecules in the air around a person without requiring them to blow directly into a tube. When combined with drug-detection technology, these tools allow for faster screening of multiple vehicles during a single blitz.

Experts said the goal is to close a regulatory gap where drivers who were not intoxicated by alcohol, but were impaired by other drugs, could previously avoid detection during standard traffic stops. The integration of these devices represents a new investment priority for the Brazilian government as it seeks to modernize its traffic safety infrastructure.