We define populism as a platform proposing a policy based on a mis-specified model of the world, a simple alternative worldview. Voters’ trust in the mainstream political class evolves over time and depends on traditional politicians’ performance once in office. Crucially, we assume this political distrust behaviourally increases the trust in simple alternative worldviews proposed by populists. Traditional politicians are aware of this risk and try to prevent it. Using this novel framework, we study when voters elect populist politicians, how populist and their alternative worldviews survive/recur and their long-run effect on several measures of voter’s welfare. We show the link between distrust and alt-truth gives rise to “populist cycles” where trust never converges to its true level. However, cycles can be welfare improving for the voter. The increased pervasiveness of alt-worldviews is not always detrimental as it has a disciplining effect on mainstream politicians.

Keywords: Policy Complexity, Populist Trap, Behavioural Voters. JEL Classification: D72, D83, D9