I am going to tell you a shocking story of profound greed, treachery and deceit. An entire industry has colluded since its very birth to endanger all of humanity for money.

The fossil fuel industry already knew in the 1980s that global warming would spell catastrophe for humanity, having carried out their own studies, only to sit on and hide the results from the world at large.

However, this story begins far earlier than that. To understand the true wickedness of this industry, and to be able to combat the vast amount of propaganda and junk science it produces, we must look at the entire history of the fossil fuel industry.

We must look to when it first began sabotaging humanity, on a topic entirely unrelated to climate change.

Our story begins in 1921 with a young engineer working for General Motors by the name of Thomas Midgley Jr. After having lost the company money after a past innovation, he was desperate to prove himself.

When he discovered that tetraethyl lead could vastly improve the efficiency of gasoline, it was therefore less important that it was a dangerous neurotoxin.

The scope to make tremendous profits from adding lead to gasoline was recognised by his bosses in General Motors, especially as in the 1920s, it had not yet been decided if fossil fuels would defeat their competition in the market. It was a time when there was innovation and research into electric cars and ethanol fuel as alternatives to conventional fossil fuels.

It was the discovery that lead could be added to gasoline which allowed gasoline to dominate the market, and the companies which got their foot in the door first, to become incredibly powerful and wealthy. Through collusion with public authorities like the US Bureau of Mines and the Public Health Service, General Motors was able to produce bogus science to cover up for the negative health effects of lead in gasoline.

The US’s supposed authority on lead in gasoline was Dr Robert Kehoe of the University of Cincinnati, paid for by the fossil fuel companies to produce false studies which gave the impression that lead in gasoline posed no health risk.

His career in covering up the truth began in 1925 at a health conference called for by the US Surgeon General, after workers died in factories producing this new leaded fuel.

Kehoe stated that leaded fuel should no longer be sold “if it can be shown... that an actual danger is had as a result...” of the addition of lead to gasoline.

When money is allowed to reign unchallenged, human survival always comes in second place

He argued that discontinuing the production and sale of this efficient fuel would be immoral on the basis of its economic value, and that therefore, proof was needed that it was dangerous first. Otherwise, Kehoe reasoned, an economic asset would be wasted, “thrown into the discard on the basis of opinions”.

This approach to science placed the burden of proof on the general public, rather on the companies and corporations gambling with people’s lives. It is a strategy employed by fossil fuel companies to this very day and has come to be known as the Kehoe Rule. It is the opposite of the precautionary principle, whereby risk and danger are avoided if there is a possibility of things going wrong due to incomplete studies, for example.

By applying the Kehoe Rule, companies which were profiting from the use of lead in fuel were able to ward off criticism and legal action, by saying that the critique was fraught with uncertainty. Whenever a study was produced criticising lead, using the Kehoe Rule, it could simply be said that more proof was required.

It was in this way, and through false studies produced by Kehoe himself, that lead was able to remain in circulation in fuel until the 1980s. Among the highlights of Kehoe’s junk science, he claimed that lead appeared naturally in the human body and that the high levels of lead in the blood of his test subjects was normal and healthy.

While the truth could not be suppressed forever, it remains remarkable and shocking that it took until the 1980s for lead to be phased out by governments from its role in the fuel economy across the developed world. It is still sometimes used in third world countries, however, which are seen as remaining markets by these industries for their leaded gasoline.

Countless lives ended before their time due to unending hunger and greed, with Kehoe covering up for their deaths starting from that fateful 1925 conference following industrial accidents.

Kehoe himself would live to the ripe old age of 99 and passed away in 1992.

The 1980s were the beginning of the end of one ugly chapter of economic history, but one conspiracy would readily be replaced by another. To fight today’s battles, it is necessary to look to the history of leaded gasoline as we have done.

Today’s battles, however, revolve first and foremost around climate change. As the door closed on leaded gasoline in the 1980s, Shell and Exxon were discovering the threat of manmade climate  change and studied the devastating effects it promised for humanity and the world in the 21st century.

Conducting their own studies, Shell and Exxon predicted how CO2 would devastate the world.

Much like those who came before them, these companies and many others colluded to keep the truth away from the general public. What seems like unimaginable evil when seen in isolation makes perfect sense today when we see how this is merely more of the same. Just as the truth about smoking and leaded gasoline were hidden away, so it has been the same for fossil fuels and global warming.

The fact that there is so much scepticism around climate change in many segments of society today is a result of expensive propaganda campaigns from the fossil fuel industry. The Kehoe Rule has been taken up by new generations of fraudulent scientists, funded by dirty money from the very same industries they defend.

These new Robert Kehoes of the 21st century wear the guise of credibility and work for grand-sounding think tanks and legitimate looking organisations. Yet, like Kehoe and his merry men before them, these think tanks and policy institutes present distorted versions of reality, using the same arguments that were used a century before to prioritise economic interests over the survival and well-being of the human race.

Their arguments are then taken up by the scientifically illiterate across the world, who then vote for politicians who call climate change a conspiracy. As it turns out, there are conspiracies after all. The conspiracies have tremendous marketing budgets, and they are readily identified by the fact that they protect the fossil fuel industry at the expense of the entire world.

We must no longer allow these companies to dictate global politics or economics, endangering and impoverishing us all. We must stand up to them, for it is clear to see that when money is allowed to reign unchallenged, human survival always comes in second place.

Timothy Alden is deputy leader of the Democratic Party.