A Windham resident has been sentenced in Portland's U.S. District Court for conspiring to tamper with environmental monitoring devices on diesel vehicles, violating the Clean Air Act, and obstructing an Environmental Protection Agency (EPA) investigation.
Isaac Allen, 35, received a three-year probation sentence and a $40,000 criminal fine from U.S. District Judge Nancy Torresen. This penalty aligns with the maximum recommended by the United States Sentencing Guidelines for Allen’s offense level. As part of his probation conditions, Allen must ensure that all vehicles he owns or is associated with comply with the Clean Air Act by maintaining required emissions controls and a functioning on-board diagnostic system (OBD). Allen entered a guilty plea on November 20, 2024.
The Clean Air Act aims "to protect and enhance the quality of the Nation’s air resources so as to promote the public health and welfare and the productive capacity of its population." It mandates that diesel trucks have operational systems to limit harmful emissions that could endanger public health. The act also requires these systems be monitored by an OBD to detect any non-functional or removed emissions control components. Tampering with an OBD is considered a felony.
Between January 2017 and September 2020, Company A, which disabled emissions control systems on diesel engines, referred customers to Allen for downloading illegal software known as “tunes.” These tunes prevented OBDs from recognizing disabled emissions controls. Allen downloaded these illegal tunes onto vehicles' OBD ports via the internet. In response to an EPA request for information under the Clean Air Act, Allen submitted false documentation understating the number of illegal tunes installed.
The EPA estimates that using emissions control defeat devices can increase air pollution emissions from a single diesel pickup truck by 10-100 times. Diesel exhaust contains acidic and hydrocarbon gases harmful to human health, causing issues such as eye irritation; respiratory inflammation; breathing difficulties; reduced lung function; increased susceptibility to respiratory infections; and asthma aggravation.
This case was referred to the EPA by Maine State Police and investigated by EPA’s Criminal Investigation Division.