On Wednesday, June 5, Pennsylvania’s Commonwealth Court had its first hearing to consider arguments in the case Peters Brothers, Inc., et. al. v. DEP et. al. challenging Pennsylvania’s delegation of heavy duty truck emissions rules to California’s Air Resources Board. Below is a summary of this hearing.

With the help of attorneys at the Pacific Legal Foundation, PMTA and four of its members – Peters Brothers, Inc., H.R. Ewell, Inc., Kenworth of Pennsylvania, and Transteck, Inc. – filed this lawsuit against the PA Department of Environmental Protection (DEP) and the Pennsylvania Environmental Quality Board for its attempt to outsource its regulations on truck sales to California regulators. PA adopted CARB’s rules in 2002, and they automatically update every time CA’s rules change.

These updates include increasingly more stringent emissions standards for heavy diesel engines over the coming years, along with more costly warranty requirements when buying new trucks.

Central to PMTA’s argument is that the “rolling incorporation” of California’s rules violates separation of powers because it cedes the power to make law to bureaucrats at CARB who are not accountable to the people of PA. Pennsylvania citizens and businesses should have the ability to comment and raise objections before such rules are put into place or changed in PA.

In the June 5 hearing, the full Commonwealth Court considered DEP’s preliminary objections to PMTA’s arguments. At issue was whether the case should be permitted to continue or whether it should be dismissed as premature. The attorney for DEP argued:

1. PMTA and its members have no standing because the regulation isn’t currently being enforced. (DEP has  delayed enforcement of the new CARB rule until MY 2027.)
2. A Pennsylvania statute blocks anyone from bringing a lawsuit unless and until DEP initiates an enforcement action.
3. The Clean Air Act requires Pennsylvania to walk in lock-step with California in order to comply with national air quality standards.

Judges on the court asked DEP’s attorney a number of questions, including whether this was an improper delegation of authority to another state. He answered that the initial CARB regulation, promulgated in 2002, was properly approved under PA’s Regulatory Review Act. And he argued that there was no constitutional problem here because Pennsylvanians can still participate in California’s rulemaking process by submitting comments on California Air Resource Board rules.

One judge noted the impact of the rule on the trucking industry, including cost, warranty, plans for the future, budget, and the ability to get equipment. She asked if it was fair that PA companies don’t have the ability to comment on something that impacts them so much. She also expressed concern that truckers are precluded from having any options to challenge the rule. The DEP attorney answered that truckers can bring a challenge after DEP begins enforcement in 2026.

Pacific Legal Foundation attorney, Luke Wake, argued for PMTA. He framed this as a case about whether Pennsylvania regulators can outsource lawmaking power to California, such that Pennsylvanians have no say in the rules affecting their affairs.

Wake was immediately asked why Pennsylvania’s statutory bar on pre-enforcement lawsuits should not preclude this case. He answered that the bar on pre-enforcement lawsuits only implicates cases contesting the Environmental Quality Board’s 2002 finding that more stringent emission standards were required to ensure compliance with federal air standards at that time. PMTA is not contesting that 2002 finding, but is instead challenging the Board’s authority to adopt a rolling incorporation of California law—which is not implicated by the statutory bar on pre-enforcement lawsuits. And further he argued that there would be a due process problem, under the federal Constitution, if Pennsylvania law precludes PMTA’s lawsuit. One should not have to violate state regulation and “bet the farm” in order to have their day in court.

Separately, Wake affirmed that PMTA has a ripe case because CARB’s warranty requirements are already in effect, and any company that ignores those California standards risks the possibility of lawsuits. Further, he argued that PMTA members need relief now because DEP has already confirmed it intends to begin enforcing new California standards beginning for Model Year 2027 vehicles; given that dealers will be negotiating presales for 2027 vehicles next summer there is no reason for the court to delay hearing PMTA’s arguments.

As to the legality of this rolling incorporation of California standards, Wake stressed that the Constitution requires that the General Assembly must make the fundamental policy decisions affecting Pennsylvanians and that the Assembly must always provide a governing standard when delegating rulemaking authority. And, as he argued, the Pennyslvania Air Pollution Control Act cannot be interpreted as allowing for a rolling incorporation because that would mean that the Assembly has decided nothing.

If the Board really has the power to follow California wherever it might go then the General Assembly has decided upon no policy or governing standard for whether or under what conditions Pennsylvania should follow California law. As he put it, that’s opening Pandora’s Box. No one in 2002 knew what standards California would impose in 2024. And no one can know what California might do in the future. As he warned, California could ban the combustible engine entirely and that would become law in Pennsylvania automatically if this rolling incorporation stands.

Wake next argued that, properly interpreted, PA’s Air Pollution Control Act prohibits “rolling incorporation” of CARB rules. As he put it, the Act requires the Board to make a fresh determination as to whether it makes sense to adopt California new standards with eyes wide open—knowing all the facts, as they exist today. For example, the Act requires that the Board must consult with PennDOT whenever its adopting rules to regulate vehicle emissions. And, as he put it, it makes no sense to say that one time consultation in 2002 was good enough because there was no way that PennDOT (or Pennsylvanians who submitted comments at that time) could have offered meaningful feedback on yet unknown standards.

Finally, Wake emphasized that PA law requires that Pennsylvanians must be allowed to comment on any new rule—which means any change in standards that have the “effect of a binding norm.” Therefore, since California’s new emissions standards have changed the legal obligations of companies in Pennsylvania, there should have been opportunity for Pennsylvanians to weigh in before those standards became effective here in the Keystone State.

During the DEP attorney’s rebuttal, he was asked whether there might be an exception to the ban on pre-enforcement challenges when there is a question about the constitutionality of a rule. The DEP attorney responded that the law doesn’t provide this exception because it prioritizes public health. He also doubled-down on his argument PMTA’s concern about third party lawsuits is speculative.

Following the hearing, PMTA and its members await the court’s decision about whether the case may proceed.