The Environmental Protection Agency isn’t going after polluters like it used to.

In its annual enforcement report released in early February, the agency revealed that it collected just $69 million in civil and administrative penalties from polluters in 2018, the lowest in more than a decade. The agency also collected just $88 million in criminal fines, down from $3 billion in fines in 2017.

The report noted that the totals can change dramatically year to year because of big cases, like the Volkswagen emissions cheating settlement that led to $4.3 billion in civil and criminal penalties in 2017.

But according to government watchdog groups, the drop off in fines in 2018 is part of a broader pattern under the Trump administration of lax enforcement of environmental laws.

A January report from Public Employees for Environmental Responsibility (PEER), an advocacy group for public sector workers who deal with environmental issues, shows that the number of criminal cases the EPA referred to the Justice Department under President Trump is at the lowest level in 30 years:

It follows a 2018 report from the Environmental Integrity Project, which found a massive drop in the amount of fines Trump’s EPA collected from polluters relative to the past three administrations during the same time frame.

Both reports make the case that the EPA is neglecting its mission and letting bad actors off the hook. That, in turn, could lead more scofflaws to ignore critical air, water, and soil protection rules.

“The deterrent effect of these statutes gets limited,” said Jeff Ruch, the executive director of PEER. “Arguably, if they’re ignored altogether, you have pollution that goes on unabated.”

A big part of the EPA’s job is to go after individuals, businesses, and even local governments that violate environmental regulations. That can mean assessing a civil penalty for a company that doesn’t refine fuel properly. It can also mean prosecuting an auto engineer conspiring to cheat emissions standards, leading to federal prison time.

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Generally, the cases referred for criminal prosecution involve actions that directly harm public health. But that requires the EPA to follow up on leads, analyze the evidence, and build a legal case.

One major reason this kind of enforcement has been down in recent years is that there’s been a big drop-off in investigations by its Criminal Investigation Division, the armed law enforcement branch of the EPA whose agents are trained to fight environmental crime.

In 2017, the number of agents at the division fell to 147, below the legal minimum of 200 set out in the Pollution Prosecution Act of 1990. That’s less than half the tally of agents employed in 2003.

“There’s a direct relation between personnel and the cases you can prosecute,” Doug Parker, a former EPA career employee who led CID under President Obama, told me. With fewer investigators to pursue leads, “you are absolutely missing cases.”

However, the Justice Department also has discretion over which cases it chooses to prosecute out of the cases it receives from the EPA. So a referral is only the first step in advancing a case against a polluter. “If you look at the data, they decline a healthy percentage of the referrals from the EPA,” said Ruch.

Over the past 32 years, the Justice Department prosecuted between 24 percent and 63 percent of the cases it received from the EPA in a given year. However, there were just 62 convictions in fiscal year 2018, the fewest since 1995.

Many of the cases underway now under the current EPA started under the prior administration, Parker noted. “Everything that I have seen announced in terms of substantive prosecutions have been cases that originated in the Obama administration,” he said. “There is little that I’ve seen that is not an Obama-era investigation.”

When asked for a comment about the decline in enforcement, an EPA spokesperson referred me to an EPA statement on the Fiat Chrysler settlement on emissions cheating allegations announced in January. The settlement requires the company to recall and repair vehicles that were equipped with a defeat device to fool emissions tests. Fiat Chrysler also has to pay a civil penalty of $305 million.

The statement explains the EPA’s enforcement strategy:

The [Fiat Chrysler] settlement also demonstrates how enforcement accomplishments for each year are highly influenced by large cases. The civil penalty for the FCA case alone is more than four times greater than all the civil penalties collected in FY2018. This case also demonstrates that while our overall number of case conclusions declined slightly in FY2018 from 1,978 to 1,818 cases, EPA is continuing to direct its resources to the most significant and impactful cases. For example, the cases EPA concluded in FY2018 required regulated entities to address over 809 million pounds of waste and pollutants, an increase of more than 40% over FY2017. Similarly, while the dollar value of Superfund cleanup commitments, oversight costs, and cost recoveries obtained in FY2018 ($613 million) is lower, those numbers also are greatly impacted by a few cases. In FY2018, EPA used its Superfund enforcement tools to facilitate cleanup and redevelopment at over 150 sites.

In essence, the EPA is arguing that the agency is going after the big fish — that the number of cases is down, but the impact of the cases it does pursue, in terms of settlements and pollution avoided, is up.

Susan Bodine, assistant administrator of the EPA’s Office of Enforcement and Compliance Assurance, told a House committee on Wednesday that the amount of fines doesn’t reflect the extent of the EPA’s work on fighting pollution. “A strong environment program doesn’t mean we have to collect a particular dollar amount or pick up a number of penalties,” she said.

Acting EPA Administrator Andrew Wheeler made a similar point in his January confirmation hearing to become the permanent administrator. “In Fiscal Year 2018, EPA enforcement actions required the treatment, disposal, or elimination of 809 million pounds of pollutants and waste – almost twice as much as compared to 2017,” he said.

Ruch isn’t convinced. He said the EPA should be able to fight big and small cases at the same time, and that the reduced number of referrals reflects a lower priority on enforcement under the current administration. “We view enforcement as a core part of their mission,” he said.

And Fiat Chrysler’s emissions cheating was first uncovered by the EPA in 2015. The settlement is also a civil penalty, not a criminal penalty.

At the same time, the EPA is pursuing an aggressive policy agenda of rolling back and relaxing environmental regulations: greenhouse gas limits, mercury regulations, and clean water authority, among others.

By changing the rules, the EPA is changing what counts as a violation in the first place. That means if the Trump administration’s changes stick and aren’t undone in the courts, we may see even fewer prosecutions in the future.