Judge cuts sentence in 1991 Boston bombing case (2021)

Originally published May 11, 2021. Statements about the law were updated in October 2026; the box below gives today’s rules.

What the law says now (October 2026). A federal judge can reduce a sentence for “extraordinary and compelling” reasons (reasons that are especially unusual and convincing). You must first ask the warden in writing. You can file in court 30 days after the warden gets the request, or sooner if you finish the Bureau of Prisons’ appeals (18 U.S.C. § 3582(c)(1)(A)). The judge also weighs the sentencing factors in 18 U.S.C. § 3553(a). See who may seek compassionate release.

Changes in sentencing law. In Rutherford v. United States (May 28, 2026), the Supreme Court held that when Congress makes a sentencing change non-retroactive (meaning it does not apply to people already sentenced), such as the First Step Act’s end of “stacked” § 924(c) sentences, the gap between an old sentence and today’s sentence cannot be an “extraordinary and compelling” reason, alone or combined with other reasons. Some older posts here describe court wins on that theory; those wins are history, not today’s law.
Claims that the conviction was wrong. In Fernandez v. United States (May 28, 2026), the Supreme Court held that arguments that a conviction is invalid (for example, innocence or trial errors) must be raised in a motion under 28 U.S.C. § 2255, not in a compassionate release motion.
COVID-19 and outbreaks. Today a court looks at whether the prison is affected, or at imminent risk of being affected, by an ongoing infectious disease outbreak or public health emergency, and whether the person faces a higher risk of severe illness or death that cannot be reduced in time (U.S.S.G. § 1B1.13(b)(1)(D)).

Outcomes vary. A past result does not predict or guarantee the outcome of any other case.

In May 2021, a federal judge in Massachusetts reduced Alfred Trenkler’s sentence to 41 years. The court did not release him right away, but it found that a shorter sentence was fair, in part to address the gap between his sentence and his co-defendant’s.

sentencing reduction

United States v. Trenkler

United States District Court for the District of Massachusetts

2021 U.S. Dist. LEXIS 87567

Background of the case

Alfred Trenkler, 65, has spent 28 years in prison. His convictions came from his role in an October 28, 1991 bombing in Roslindale, Massachusetts that killed one Boston Police Department Bomb Squad officer and maimed a second officer.

Trenkler asked for compassionate release, a process that lets a prisoner ask the court to reduce a sentence for “extraordinary and compelling circumstances.”

This was not his first challenge. He has maintained his innocence since the crime and has challenged his sentence on several grounds. He claimed he was sentenced unfairly, that he faced homophobia during his trial, and that an alleged confession to a cellmate should not carry weight in court.

The case was hard to sort out in court because the bomb went off by accident, which made “intent to kill” difficult to prove.

The government’s theory at trial was that Trenkler and his co-defendant, Thomas Shay, Jr., conspired to build a bomb and place it under a vehicle belonging to Shay, Jr.’s father, Thomas Shay, Sr., intending to kill Shay, Sr. The bomb went off accidentally after Shay, Sr. called the Boston Police Department Bomb Squad to the scene. One officer was killed and another was badly injured.

At trial, the government offered circumstantial evidence tying Trenkler to the bomb. This included evidence that he made a remote-control explosive device with similar features in Quincy, Massachusetts in 1986. After an eighteen-day trial, the jury convicted Trenkler on all three counts.

Trenkler was also sentenced by the judge, when the jury was supposed to decide his sentence. The court found this was a procedural error that did not affect whether he was guilty. Trenkler maintains that the error led to an unfair and improper sentence.

What he argued

After nearly 30 years in prison, Trenkler filed his motion for compassionate release. At the time, he pointed to several factors: the COVID-19 pandemic (especially given his documented heart condition), how much longer his sentence was than his co-conspirator’s, his unlawfully imposed life sentence, and questions about his guilt.

What the court decided

The court agreed that Trenkler’s age, smoking history, overweight-to-obese BMI, hypertension, and heart condition put him at higher risk of severe illness or death if he caught COVID-19 before being vaccinated.

But he had received his first shot of the Moderna vaccine, and conditions at his prison had greatly improved. So the court concluded that his COVID-19 risk did not rise to the level of extraordinary and compelling circumstances.

On “intent to kill,” the court could not conclude that the jury found Trenkler intended to kill Shay, Sr. But it said a bomb like this clearly had a very high potential to kill or injure.

The court noted that Trenkler has had no significant disciplinary problems in prison and is statistically very unlikely to reoffend. It did not reduce his sentence to time served. But it found a sentence reduction was prudent, noting that it would address the disparity between Trenkler’s sentence and Shay, Jr.’s.

How the court set the new sentence

The court put Trenkler’s statistical life expectancy at about 83 years, or 18 more years. With that in mind, it found that 41 years would reflect the seriousness of the offenses, promote respect for the law, and provide just punishment, while taking into account Trenkler’s history and characteristics.

If he serves the additional 13 years, Trenkler will be about 78 when released. With good time credit, he will likely be in his early 70s.

When he is released, Trenkler plans to live with family in Maine. The court noted that release at that point will let him get the medical care he will likely need outside prison.

If you want help with a compassionate release request, book a consultation.