SouthernWorldwide.com – President Donald Trump has issued pardons to nine individuals convicted of tampering with diesel engine emissions control systems, a violation of the Clean Air Act.
On Friday, Trump announced six of these pardons via Truth Social. He stated that the individuals had been “persecuted by the Biden Administration” and unfairly punished for “fixing their car.”
These modifications involve reprogramming trucks to bypass federally mandated emissions controls and disable warning diagnostics. Without these systems, many diesel trucks enter a “limp” mode, severely restricting their speed, sometimes down to 5 mph, until the emissions system is functional again.
The Clean Air Act violations are significant. These devices, often referred to as “defeat devices,” are designed to circumvent environmental regulations.
The Environmental Protection Agency (EPA) acknowledges that failures in emissions control systems are common and have historically caused considerable problems for truckers and farmers.
Consequently, there is a high demand and willingness to pay substantial amounts to mechanics who can disable these emission-limiting systems.
One of the pardon recipients, Matthew Geouge, operated two companies that sold these illegal tuning devices. His plea agreement from December 2021 indicated that his firms generated over $10 million solely from the sale of these devices.
Emissions-capping technology, particularly Diesel Exhaust Fluid (DEF) systems, is also known to malfunction in extremely cold weather conditions.
Brad Bylsma, a state equipment fleet manager for the Alaska Department of Transportation and Public Facilities (DOT&PF), commented in March that DEF systems represent a “significant portion of our maintenance issues and costs” for state-owned diesel vehicles.
Frederic Sifuentes, president of an Alaska-based transportation service, offered a more direct assessment of the issue.
“The percentage of breakdowns we have here in Alaska with the DEF systems is roughly 85 percent of the time,” he stated, highlighting the widespread nature of the problem in harsh climates.
Another individual granted a pardon, MacKenzie “Mac” Spurlock, was a mechanic in Alaska who modified emissions controls for vehicles specifically to address these operational challenges, according to Senator Dan Sullivan of Alaska.
Senator Sullivan described a raid on Spurlock’s business, Matanuska Diesel, stating, “Four years ago, about 30 armed EPA agents conducted a military-style tactical raid of Matanuska Diesel, owned by Mac Spurlock — a devoted husband and father, small business owner, and veteran of the Alaska Air National Guard.”
He further explained that Spurlock’s shop had assisted trucking businesses by modifying several diesel emissions-control systems. These modifications were necessary due to a “one-size-fits-all Obama-era emissions regulation” and ensured that the vehicles could operate without shutting down in Alaska’s severe subzero temperatures.
The other individuals who received pardons for similar offenses include Ryan and Wade Lalone, Tim Clancy, Joshua Davis, Barry Pierce, Aaron Rudolf, and Jonathan Achtemeier, as reported by CBS News.
In a previous development, in late January 2026, the Trump administration announced its intention to cease pursuing criminal charges against manufacturers, distributors, and users of defeat devices. However, civil penalties could still be imposed.
