At a time when the Environmental Protection Agency has tripled the number of bodyguards for the administrator, the agency’s cases brought against polluters is in “free fall,” according to a study released on Thursday by the advocacy group Public Employees for Environmental Responsibility.

The number of staff devoted to such investigations has also dropped, the group said. “Virtually every measure of criminal enforcement under Pruitt is lower than it has been since the 1990s – and sinking,” said a release from PEER Executive Director Jeff Ruch.

As of April 2018, the number of EPA criminal investigators had dropped to 140, one-fifth fewer than in 2012, the group said. The agency has shed seven agents just since August 2017, PEER noted. “The current EPA force-level is also well below the minimum of 200 agents required by the 1999 U.S. Pollution Prosecution Act,” PEER added.

The number of cases referred for prosecution by the Justice Department in fiscal 2017 “is the lowest in nearly 30 years and is on pace through the first seven months of fiscal 2018 to go even lower,” the advocates said. The study found that prosecutions, convictions and prison sentences in cases uncovered by EPA are about half the totals in 2001. Only 31 defendants were charged in the first half of 2018, compared to 139 in 2017.

One reason for the dropoff, the group charged, is that Pruitt centralized prosecution referrals, transferring authority from the Criminal Investigation Division to political appointee Susan Bodine, assistant administrator for EPA’s Office of Enforcement and Compliance Assurance.

PEER combined the new numbers with criticism of Pruitt for his reported overspending on amenities and use of agency staff for personal errands. “We need more agents investigating corporate pollution crimes rather than acting as personal servants for an administrator with an apparent Napoleon complex,” Ruch said. “Scott Pruitt keeps talking about returning EPA to its ‘core originalism’ but nothing is more core to the EPA mission than enforcing our nation’s pollution laws.”

An agency spokeswoman disagreed with the findings. “Administrator Pruitt is committed to enforcing the law and working with our law enforcement partners and the Department of Justice to punish criminals,” she said in a Friday statement to Government Executive. “The change in the number of criminal enforcement agents has occurred over a number of years, and does not reflect any reduction in this administration’s commitment to enforcing the law against wrongdoers.”

The agency has said it is on track to hire more investigators and is focusing on the most egregious and complex cases for enforcement, though decreasing resources remain an issue.

Pruitt’s personal security expenses, meanwhile, were reported to total $4.6 million, according to documents obtained under the Freedom of Information Act and published Wednesday by The Intercept, far more than was spent by preceding EPA chiefs.

In addition, President Trump’s new government reorganization plan released on Thursday, according to ABC News, could jeopardize Pruitt’s security arrangements by centralizing agency security under the U.S. Marshals Service.