Leading US environmental campaigners have joined a diverse line-up of pressure groups to demand a federal investigation into allegations that the oil giant ExxonMobil illegally covered up the truth about climate change.



Earlier in the week, first Bernie Sanders and then Hillary Clinton, the leading Democratic presidential candidates, called for the US government to announce an official investigation.

On Friday morning, 350.org, an environmental movement, issued a letter signed by climate campaigners, civil rights organizations, indigenous people’s groups and others, calling on US attorney general Loretta Lynch to investigate.

The letter cited “revelations that the company knew about climate change as early as the 1970s, but chose to mislead the public about the crisis in order to maximize their profits from fossil fuels”.

The letter was signed by groups such as the Environmental Defense Fund, Friends of the Earth, the Natural Resources Defense Council, Greenpeace and the Sierra Club, as well as bodies such as the Indigenous Environmental Network, which promotes environmental and economic justice issues affecting indigenous communities.

The Foundation of Women in Hip Hop, which has a stated goal of “sharing a love of the arts” and influencing perceptions about the roles of women involved with hip-hop music, also signed the letter. So did the National Audubon Society, which seeks to protect birds and their habitats, and the Ecumenical Poverty Initiative, which aims to “mobilise the faith community to end the scandal of poverty in the US”.

Leaders of the 49 campaign groups signed the letter, which charged: “The corporation knew about the dangers of climate change even as it funded efforts at climate denial and systematically misled the public.”

The appeal for action was lent extra weight by the signature of James Hansen, now the director of the climate science awareness and solutions programme at the Columbia University Earth Institute in New York but previously a climate researcher for Nasa for more than 30 years. There, he raised the alarm about climate change and became one of the world’s most renowned scientists in the field.

The letter also cites an investigation by Inside Climate News and further revelations by the Los Angeles Times which accused ExxonMobil of deception over global warming and the influence of humankind and fossil fuels.

The letter continues: “Given the damage that has already occurred from climate change – particularly in the poorest communities of our nation and our planet – and that will certainly occur going forward, these revelations should be viewed with the utmost apprehension. They are reminiscent – though potentially much greater in scale – [of] similar revelations about the tobacco industry.”

Members of Congress have called for a federal investigation. Eight days ago Sanders, a Vermont senator, echoed such calls and accused the company of lying about climate change since the 1970s.

On Thursday, Clinton, the Democratic frontrunner, added her voice. Responding to a question about whether the company should be investigated, she said: “ Yes, yes, they should. There is a lot of evidence they misled.”

Hansen, however, recently called Clinton’s proposed climate initiative “silly”. It focuses more on subsidies for solar panels and renewable energy than on pricing out fossil fuel use.

ExxonMobil has denied any wrongdoing.