This paper seeks to clarify how the descriptive legitimacy of the government could be undermined by distrust at different levels, using the case of Hong Kong as an example. I present two theoretical accounts of trust. The first type, trust as encapsulated interest, is reduced to the rational belief that the government has interests in acting trustworthily, performing the trusted tasks. Such trust is agent-neutral, operates at the institutional level. The second type of trust is attitudinal, based on the belief that the government would respond to citizens' reliance in goodwill. This type of trust is agent-relative. Its upkeep is highly sensitive to the attitudes evinced in instances of how political power is exercised. The anti-extradition bill movement in HK is a case in point that shows how the political structure of the HK government and individual cases of its power exercise jointly eroded these two types of trust and, as a consequence, created a unprecedented legitimacy crisis.