Regulation of the environment is often characterized as a polarizing issue that pits public health against economic growth. Although researchers have examined the decisions of federal district court judges in environmental civil penalty cases and examined the decision making of administrative law judges (ALJ), there has been no research which has examined factors that influence ALJ decision making in environmental civil penalty cases at the Environmental Protection Agency (EPA). I theorize that ALJ decisions, like federal district court judge decisions, are a function of personal policy preferences, hierarchical controls by higher courts, separation of powers influences, and case and defendant characteristics. Results demonstrate that the size of civil penalties issued by ALJs at the EPA is influenced by personal policy preferences, political constraints via Congress, hierarchical control by the Environmental Appeals Board (EAB) and the Supreme Court, litigant characteristics, and case characteristics. Ov...