Given the potential attitudinal and behavioral impact of Anthropogenic Global Warming (AGW) conspiracy beliefs, it is important to understand their causes and moderators. Here, two explanations for the variation in these beliefs are engaged: the first is the choice among elites to frame AGW using the phrase ‘global warming’ (GW) as opposed to ‘climate change’ (CC); the second is partisan motivated reasoning. A theory is then developed about the role of trust in moderating the impact of the two frames on AGW conspiracy beliefs. In the case of CC, which is perceived as less severe than GW (and is therefore less identity threatening among Republicans), it is hypothesized that trust will moderate hoax beliefs among Republicans. In the case of GW, where the implications of existence beliefs have policy consequences that are more unpleasant, motivated reasoning will ‘win out’, and trust will not moderate conspiracy endorsement among Republicans. The results from an original question framing experiment are consistent with the author’s hypotheses. Whilst trust is a welcome commodity to those looking to persuade citizens to support AGW-ameliorating policies, it is not a cure-all, especially in the face of elite partisan cues that edify pre-existing attitudes/identities and arouse a strong desire to engage in motivated reasoning.