Through the comparative analysis of the participatory mechanisms established in Bolivia, Ecuador and Venezuela, this study explores under which conditions such mechanisms are more likely to deepen or undermine democracy. While the informal participatory mechanisms established in Bolivia have produced, though imperfectly, significant democratic benefits, in Ecuador and Venezuela crucial participatory mechanisms have appeared to favour the concentration of power in the executive, contributing to the strangulation of representative institutions, the erosion of the separation of powers and the development of government-dominated social groups. By shedding light on the undemocratic manipulation of participatory mechanisms, an area still largely unexplored, this study contributes to a better understanding of the risks and opportunities associated with the deepening of democracy.