This article describes the process of legal contention between civil society, political parties, and state institutions for the baldíos lands in the Colombian Altillanura region in the last two decades, a region considered the country’s “last agricultural frontier.” The article focuses on the dual and sometimes contradictory roles of the state institutions, both as facilitators of baldíos grabbing and as guarantors of the peasants’ legal land rights. It analyzes the different attempts by the Colombian government to remove the legal limitations to land accumulation and the resistance put up by civil society and the political parties, which resorted to the existing legal mechanisms to deactivate those attempts. The results reveal the two-sided role of the state: while the government introduces legal changes to facilitate baldíos grabbing, state bodies are actively denouncing and sanctioning illegalities or ruling in favor of peasants deprived of their lands.