Motor vehicles; creating the Oklahoma Diesel Engine Freedom Act. Emergency.

SB 457, the Oklahoma Diesel Engine Freedom Act, nullifies federal requirements for diesel exhaust fluid in vehicles operating solely within Oklahoma, declaring such rules unconstitutional under the 10th Amendment. It prohibits state agencies from enforcing federal diesel fluid mandates and legalizes the sale and use of diesel engines that do not require diesel exhaust fluid within the state. The bill imposes civil fines of up to $5,000 per violation and employment termination for state officials who enforce federal rules. It repeals Oklahoma’s existing law (47 O.S. 2021, Section 12-423) governing emission control systems and requires non-diesel-exhaust-fluid engines to be labeled for intrastate use only.