Marquette Heights Felon Sentenced to 57 Months in Prison for Possession of a Stolen Firearm and Unregistered Destructive Devices

PEORIA, Ill. – A Marquette Heights, Illinois, man, Dalton Lee Mattus, 35, was sentenced on March 5, 2025, to an aggregate 57 months’ imprisonment, to be followed by three years of supervised release, for possessing a firearm as a felon, possessing a stolen firearm, and possessing an unregistered destructive device.

At the sentencing hearing in front of Senior U.S. District Judge Michael M. Mihm, the court was informed that Mattus had multiple prior criminal convictions within Tazewell and Peoria Counties that prohibited him from possessing a firearm.  In May 2024, he was the passenger in a car that was stopped by Pekin Police Department officers. During the traffic stop, the officers confiscated a locked bag from the car. After obtaining a search warrant for the bag, they found a stolen Springfield Armory XD-S .45 caliber semiautomatic pistol and two unregistered destructive devices. The devices were made from cardboard tubing, metal BBs, and chemical powder used to make explosives. The officers also obtained a search warrant for Mattus’s residence, where they found three additional unregistered destructive devices, along with materials to make several more. Officers also seized 50 rounds of live ammunition and equipment used to assemble and disassemble firearms.

In sentencing Mattus, Judge Mihm commented that while this was a very serious case, what was most troubling was that the explosives were homemade and were intended to harm others. The judge commented that this is “about as bad as it gets.”

Mattus was arrested by the Pekin Police Department in May 2024, and a federal complaint was filed two weeks later, followed by a federal indictment in June 2024. He entered a guilty plea in October 2024.

The statutory penalties for possessing a firearm as a felon are not more than 15 years’ imprisonment. The maximum term of imprisonment for possessing a stolen firearm and possessing an unregistered destructive device is ten years’ imprisonment. Each count carries up to a three-year term of supervised release.

The Peoria Area Federal Firearms Task Force, comprised of agents from the Bureau of Alcohol, Tobacco, Firearms and Explosives; the Peoria Police Department; the Peoria County Sheriff’s Department; Illinois Department of Corrections; and the Illinois State Police, investigated the case. The Pekin Police Department and Tazewell County Sheriff’s Department also participated in the investigation. 

The case against Mattus is part of Project Safe Neighborhoods (PSN), a program bringing together all levels of law enforcement and the communities they serve to reduce violent crime and gun violence, and to make our neighborhoods safer for everyone. On May 26, 2021, the Department launched a violent crime reduction strategy strengthening PSN based on these core principles: fostering trust and legitimacy in our communities, supporting community-based organizations that help prevent violence from occurring in the first place, setting focused and strategic enforcement priorities, and measuring the results.