Territorial capture by illicit economies along Brazil’s Amazon BR-319 highway

The BR-319 highway in the Brazilian Amazon connects Porto Velho, in the deforestation arc, to Manaus in Central Amazonia, crossing one of the world’s largest tropical forest blocks. Opened in 1976, the highway was abandoned in 1988 following economic unviability and loss of trafficability, and maintenance resumed in 2015 under a new license. More recently, Brazil’s General Environmental Licensing Law (Law No. 15,190/2025) introduced simplified licensing provisions for maintenance, improvement, and paving of pre-existing infrastructure, creating a new regulatory context for BR-319 consolidation without prior establishment of adequate territorial-governance and enforcement safeguards. We combined satellite land-use monitoring, cattle supply-chain records, field validation, documentary evidence, and directed network analysis to examine associations among road accessibility, illicit land occupation, commodity chains, and political–institutional factors. Within the 40-km road-influence buffer, deforestation shifted from a declining pre-2015 trend of − 565 ha yr⁻ 1 to a post-2015 increase of + 2,965 ha yr⁻ 1 , significantly diverging from the non-road-connected Trans-Purus controls of Pauini ( p = 0.029) and Tefé ( p = 0.039). Post-2015 pasture formation exceeded 70% in Humaitá and approached 90% in Tapauá, while illegal side-road access points in Vila Realidade occurred every 10–15 km. Network analysis identified a structured relational system linking deforestation, illegal roads, land grabbing, mining, drug trafficking, cattle laundering, slaughterhouses, export markets, and political–institutional feedbacks ( R 2 = 0.67, p = 0.001). Convergent network, documentary, field, and land-use evidence indicates that increased road accessibility is associated with the territorial expansion of illicit economies. Actors embedded in or connected to these networks also occupy relational positions associated with political and institutional processes supporting licensing, regulatory changes, and paving agendas. This configuration is consistent with institutional and territorial capture, in which illicit economic interests intersect with infrastructure governance and may reinforce organized criminal networks. Given limited command-and-control, environmental-enforcement, land-tenure, and public-security capacity, the findings support reassessing and revoking licenses and legal or regulatory measures that enable further road consolidation without adequate safeguards. Governance, territorial control, environmental enforcement, public security, and protection of Indigenous and traditional territories should precede further increases in road accessibility.