Those who study climate (and the political climate debate) are well aware of how the government has presented an exaggerated case for carbon-dioxide-driven global warming: Government-supported scientists have “modeled” warming that doesn’t exist in reality; government-supported scientists have made emotional arguments; government-supported scientists have substituted unreliable temperature proxies cherrypicked to show a colder past (e.g., selected tree rings); government-supported scientists have mixed up rises in CO2 levels and heat to make it appear that rising heat came afterward, etc.
Climatologist Steven Goddard has shown that the case for manmade, CO2-driven global warming is mostly a product of knowing manipulation of past temperature data. See here.