William Earl Siebert, Pipe Bomb Possession, Florida 2022

FORT MYERS, FL – A Cape Coral man with a prior second-degree murder conviction is facing another lengthy stretch behind bars after being sentenced to 5 years and 10 months in federal prison for possessing an unregistered destructive device – a homemade pipe bomb. William Earl Siebert, 47, pleaded guilty on June 16, 2022, to the charge, and U.S. District Judge Sheri Polster Chappell handed down the sentence Wednesday.

The case unfolded after Siebert was arrested on August 27, 2019, for driving under the influence following a single-vehicle crash on Del Prado Boulevard in Cape Coral. It wasn’t the DUI that landed him in federal court, however. A search of Siebert’s wrecked vehicle revealed a chilling discovery: a fully assembled pipe bomb, meticulously rigged to a yard-stake timer. The device contained a significant quantity of explosive powder and was packed with an assortment of shrapnel, designed to inflict maximum harm.

Authorities quickly recognized the severity of the situation. Siebert’s criminal history – a prior 25-year state prison sentence for second-degree murder – painted a disturbing picture. The combination of a violent past and the possession of a dangerous explosive device triggered a full investigation by the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), alongside the Lee County Sheriff’s Office and the Cape Coral Police Department. The feds weren’t messing around.

Assistant United States Attorney Simon R. Eth led the prosecution, presenting the evidence that ultimately led to Siebert’s guilty plea. While the specifics of Siebert’s intent remain largely undisclosed, the presence of a functional pipe bomb in his possession, coupled with his violent history, spoke volumes. The device was capable of causing serious injury or death, and its illegal construction and possession are federal offenses.

Federal officials are framing the case as part of “Project Safe Neighborhoods” (PSN), a broad initiative aimed at reducing violent crime and gun violence across the country. The program emphasizes collaboration between law enforcement at all levels and community engagement. This case, they say, exemplifies the program’s goal of taking dangerous individuals off the streets and preventing further violence. But for many, the fact that a convicted murderer was back on the streets at all raises serious questions.

Siebert’s 5 years and 10 months in federal prison will likely be added to any potential parole restrictions stemming from his previous murder conviction. The ATF continues to investigate potential connections or motives behind the bomb’s construction, although details remain scarce. For the residents of Cape Coral, and for the victims of Siebert’s past crimes, the sentence offers a measure of relief, but the underlying threat of individuals with violent tendencies and access to dangerous weapons remains a stark reality.

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