The environmental statutes were passed in a world where, from the point of view of their architects, they were environmental justice statutes. But that world was disappearing as soon as the new environmental laws were written. They were written in a time that was more economically equal than the US had ever been, and they believed that trend was going to continue, and that therefore economic inequality was a problem that had been solved. We now know, thanks to the work of economist Thomas Piketty and others, that they were living at the end of an anomalous period of widely shared growth that lasted across the North Atlantic between the end of World War Two and the beginning of the 1970s. Inequality was about to reassert itself, and it has been growing more or less ever since.

Just as today’s environmental-justice critics say, the laws that govern pollution and dumps for hazardous materials don’t address how those get distributed. Leaving out distribution was a mistake that was much easier to make if you believed that the country was steadily getting more equal. The more recent environmental-justice movement arose in response to the fact that environmental harms are distributed along very familiar lines of race and poverty. Those lines were expected to become less important in the years ahead. Legislators like Muskie also said that they expected the environmental laws to be supported by other reform legislation to overcome poverty and isolation, foster public health, and make workplaces safer and communities more livable. Instead, the 1970s brought the return of inequality and the end of political support for bold social reforms.

Then it got worse. The Supreme Court removed an essential protection against disparate environmental impacts in the form of constitutional Equal Protection challenges. Between 1976 and 1979, after the major environmental statutes were largely written, the Court adopted the current constitutional standard, which requires plaintiffs claiming they have been treated unequally to show that the government action they object to was affirmatively motivated by discriminatory purpose. It isn’t enough to show that, in fact, burdens are distributed in a grossly unequal way. So unequal harms that would once have been open to constitutional challenge are now legally clear unless they violate environmental statutes—which were not written with this kind of inequality in mind.

The other charge that today’s environmental-justice movement makes is that mainstream environmentalism overemphasizes elite advocacy. This, too, is not a perennial feature of environmental law, but developed in the 1970s because of specific institutional decisions. A key part of the story is that the Ford Foundation made critical investments to shape the new groups that helped to make the field of environmental law: the Environmental Law Institute, the Natural Resources Defense Council, the Environmental Defense Fund, and others. Ford picked and cultivated its grantees to advance a vision of lawyers’ role in advocacy and social reform that historians call “legal liberalism.” Legal liberalism saw lawyers as channels for marginal voices that otherwise wouldn’t be heard in pluralist democracy. The ideal was that, if you could just get these marginalized voices their day in court, in front of an impartial decision-maker, you could ensure that their interests were respected in the decision process. In this respect, the institutions of environmental law were shaped by a conception of the legal profession that Ford was also helping to spread at the same time through law-school clinics, ABA pro-bono guidelines, and poverty-law services.