Documents released during tobacco litigation demonstrate ... the crucial role that scientists played in sowing doubt about the links between smoking … - Naomi Oreskes

This message of scientific uncertainty has been reinforced by the public relations campaigns of certain corporations with a large stake in the issue. The most well known example is ExxonMobil, which in 2004 ran a highly visible advertising campaign on the op-ed page of the New York Times. Its carefully worded advertisements—written and formatted to look like newspaper columns and called op-ed pieces by ExxonMobil—suggested that climate science was far too uncertain to warrant action on it. One advertisement concluded that the uncertainties and complexities of climate and weather means that "there is an ongoing need to support scientific research to inform decisions and guide policies". Not many would argue with this commonsense conclusion. But our scientists have concluded that existing research warrants that decisions and policies be made today.

Then-Vice President George H. W. Bush ran for president of the United States pledging to combat the “greenhouse effect with the White House effect”. 1988 was also the year in which the world nations joined together to create the w:Intergovernmental Panel on Climate Change (IPCC) to provide a scientific basis for policy action. Fossil fuel corporations might have begun to take steps to limit the damages their products caused to the global environment.
Instead, leading investor-owned fossil fuel corporations, including ExxonMobil, Shell, and British Petroleum, created the Global Climate Coalition (GCC) to oppose greenhouse gas emission reduction policies. From 1989 to 2002, the GCC led an aggressive lobbying and advertising campaign aimed at achieving these goals by sowing doubt about the integrity of the IPCC and the scientific evidence that heat-trapping emissions from burning fossil fuels drive global warming. They worked successfully to prevent the United States from signing the Kyoto Protocol after it was negotiated in 1997. When the GCC disbanded, they stated that they had achieved their goals....
Between 1988 and 2005, ExxonMobil invested over $16 million in a network of front groups that spread misleading claims about climate science. It also exploited its close relationship with the administration of President George W. Bush to pressure the administration to remove top scientists from leadership roles in the IPCC and the US National Climate Assessment and to promote federal policies driving further reliance on fossil energy

This paper assesses whether ExxonMobil Corporation has in the past misled the general public about climate change....
Our assessment of ExxonMobil's peer-reviewed publications and the role of its scientists supports the conclusion that the company did not 'suppress' climate science—indeed, it contributed to it.
However, on the question of whether ExxonMobil misled non-scientific audiences about climate science, our analysis supports the conclusion that it did....
Available documents show a discrepancy between what ExxonMobil's scientists and executives discussed about climate change privately and in academic circles and what it presented to the general public. The company's peer-reviewed, non-peer-reviewed, and internal communications consistently tracked evolving climate science: broadly acknowledging that AGW [Anthropogenic Global Warming] is real, human-caused, serious, and solvable, while identifying reasonable uncertainties that most climate scientists readily acknowledged at that time. In contrast, ExxonMobil's advertorials in the NYT [New York Times] overwhelmingly emphasized only the uncertainties, promoting a narrative inconsistent with the views of most climate scientists, including ExxonMobil's own. This is characteristic of what Freudenberg et. al. term the Scientific Certainty Argumentation Method (SCAM)—a tactic for undermining public understanding of scientific knowledge. Likewise, the company's peer-reviewed, non-peer-reviewed, and internal documents acknowledge the risks of stranded assets, whereas their advertorials do not. In light of these findings, we judge that ExxonMobil's AGW communications were misleading; we are not in a position to judge whether they violated any laws.