The US Department of Justice (DOJ) recently announced it is “exercising its enforcement discretion to no longer pursue criminal charges . . . on allegations of tampering with onboard diagnostic devices in motor vehicles” under the Clean Air Act (CAA or Act). According to DOJ, this exercise of discretion not to criminally prosecute is based on “sound enforcement principles, efficient use of government resources[,] and avoiding overcriminalization of federal environmental law.” DOJ’s announcement is an about-face from years of criminal prosecutions for identical conduct, including an increase of these prosecutions under the first Trump administration. As a result of this new policy, DOJ is now dismissing existing CAA criminal tampering cases—more than a dozen prosecutions thus far—and the decision may impact some 20 or more ongoing investigations. DOJ stated in its announcement that it intends to continue to pursue civil enforcement for tampering cases under the Act in partnership with EPA.
